Thomas Ray's paper is a fairly good resource for psychedelic receptor data, good way to hunt down other 5-HT1 agonist if mescaline is not available:
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0009019
hxxp://www.plosone.org/article/info:doi%2F10.1371%2Fjournal.pone.0009019
Other compounds that would work in place of mescaline to hit lots of the 5-HT1 receptors and even the transcendental 5-HT7 (5-HT6 hit by 25i is quite similar) receptor are:
5-MEO-DMT
5-MEO-MIPT
4-ACO-DIPT
However, many of the above compounds are illegal in many countries
other options:
4-ACO-DMT (looks like a great candidate in very low dose, else make this dose larger and 25i dose very low)
etc.
In countries where the above are not illegal? should really consider theoretically taking advantage of adding some potent low-dose 5-HT1 agonist into the 25i-nbome mix, this difference is like night and day, it is sooooo much better, if you love LSD trips (100% mind manifesting) you will love combining the nbome with 5-HT1 agonist, LSD also hits a large amount of the 5-HT1 receptors, see below.
4.00=maximum affinity for the receptor site:
5-MeO-DMT: 4.00 5ht1a, 3.69 5ht7, 3.48 5ht1d, 2.73 5ht6, 2.41 5ht1b, 2.38 D1, 1.84 5ht5a, 1.72 5ht1e, 1.58 D3, 1.57 Alpha2C, 1.55 5ht2c, 1.00 Alpha2A, 0.98 5ht2a, 0.97 SERT, 0.88 Imidazoline1, 0.86 Alpha2B, 0.82 NET, 0.78 D4, 0.73 D2, 0.69 5ht2b; 0.00: Alpha1B, Beta2, Beta1, DAT, D5, Alpha1A, Sigma1, Sigma2, CB2, KOR, Ca+Channel, M1, M2, M3, M4, M5, H2, CB1; ND: H1, DOR, MOR, NMDA
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Mescaline: 4.00 Alpha2C, 3.97 5ht2b, 3.61 5ht1a, 3.44 Imidazoline1, 3.16 5ht1e, 2.92 Alpha2A; 0.00: 5ht2a, 5ht2c, 5ht6, 5ht1d, D1, D2, D3, D4, D5, Alpha1A, Alpha1B, 5ht5a, Alpha2B, 5ht7, Beta1, Beta2, SERT, DAT, NET, 5ht1b, Sigma1, Sigma2, DOR, KOR, MOR, M1, M2, M3, M4, M5, H1, H2, CB2, CB1, Ca+Channel, NMDA
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Psilocin: 4.00 5ht2b, 3.40 5ht1d, 3.37 D1, 3.03 5ht1e, 2.88 5ht1a, 2.83 5ht5a, 2.82 5ht7, 2.82 5ht6, 2.67 D3, 2.52 5ht2c, 2.19 5ht1b, 2.14 5ht2a, 1.77 Imidazoline1, 1.74 SERT, 1.57 Alpha2B, 1.36 Alpha2A, 1.03 Alpha2C; 0.00: D2, Alpha1B, D5, D4, Beta2, Beta1, DAT, NET, Alpha1A, Sigma1, Sigma2, DOR, KOR, MOR, M1, M2, M3, M4, Ca+Channel, H1, H2, CB2, CB1; ND: M5, NMDA
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5-MeO-MIPT: 4.00 5ht1a, 3.79 5ht7, 3.74 5ht1d, 3.32 5ht2b, 2.98 5ht6, 2.85 Alpha2A, 2.61 5ht1b, 2.44 5ht2a, 2.29 Alpha2C, 2.15 Imidazoline1, 2.13 Sigma2, 2.11 5ht5a, 1.86 Alpha2B, 1.75 5ht2c, 1.70 D3, 1.55 5ht1e, 1.41 H1, 1.29 D4, 1.28 SERT; 0.00: D2, Alpha1B, D5, D1, Beta2, NET, DAT, Sigma1, Beta1, DOR, KOR, MOR, M1, M2, M3, M4, M5, Alpha1A, H2, CB2, NMDA, Ca+Channel; ND: CB1
---------------------
DIPT: 4.00 5ht1a, 3.53 Imidazoline1, 3.48 5ht2b, 2.98 SERT, 2.83 Sigma1, 2.68 Alpha2C, 2.65 Sigma2, 2.62 Alpha2B, 2.56 D3, 2.55 5ht7, 2.53 H1, 2.51 5ht1d; 0.00: 5ht2a, D4, 5ht5a, D1, D2, Alpha2A, 5ht6, D5, Beta1, Beta2, 5ht2c, DAT, NET, 5ht1b, Alpha1B, 5ht1e, DOR, KOR, MOR, M1, M2, M3, M4, M5, Alpha1A, H2, CB2, CB1, Ca+Channel, NMDA
----------------------
LSD: 4.00 5ht1b, 3.77 5ht7, 3.75 5ht6, 3.73 5ht1a, 3.70 5ht1d, 3.64 5ht5a, 3.54 5ht2a, 3.16 D3, 3.11 5ht2b, 3.11 5ht2c, 2.93 Alpha2A, 2.62 5ht1e, 2.55 D2, 2.39 D4, 2.34 D1, 2.05 D5, 1.54 Alpha1A, 1.40 H1, 1.39 Beta1, 1.05 Beta2, 0.65 Alpha1B; 0.00: KOR, DOR, DAT, SERT, MOR, NET; ND: Sigma2, Alpha2B, Alpha2C, Imidazoline1, M1, M2, M3, M4, M5, Sigma1, H2, CB2, CB1, Ca+Channel, NMDA
-----------------------
For example:
25i-nbome agonizes the following receptors [the lower the number, the greater the affinity]
5-HT2A (0.044), 5-HT2C (2), 5-HT6 (73), 5-HT2B (231), u opiate (82), kappa opiate [288]
mescaline agonizes the following receptors [4.00 = maximum affinity, 0.00 = no affinity]:
Alpha2c (4.00), 5-HT2B (3.97), 5-HT1A (3.61) Imidazoline1 (3.44), 5-HT1E (3.16), alpha 2a (2.92)
therefore, mescaline + 25i looks like:
5-HT2A, Alpha2c, 5-HT2B, 5-HT2C, 5-HT1A, 5-HT1E, 5-HT6, u opiate, kappa opiate, Imidazoline1, alpha2a.
*** Also note that 25i-nbome is the most potent 5-HT2A agonist discovered, 5-HT2A agonism while being highly visual & holding high behavioral & empathogenic characteristics, also causes a bit of low level stimulation & raises blood pressure, 5-HT1 agonism on the other hand lowers blood pressure and has a meditative, serene, tranquil, calming quality, so combining the two serves a yin & yang purpose, to balance each other out. I would never combine 25i with LSD because LSD is allready a very potent 5-HT2A & 5-HT2C receptor agonist. 25i is 100 times more potent at the 5-HT2A site than even LSD! This was shown by Nichols in his paper on 25i.
4-aco-dmt sounds like it will fully replace mescaline in combination with 25i, so long of course as the 4-aco-dmt dose is kept moderate in comparison to an added in very low dose of 25i, this ensures that all the 5-HT1 receptors are hit with more strength then the 5-HT2A & 5-HT2C are hit, ensuring that it will give psychedelic effects just like LSD, LSD also hits 5-HT1 and 5-HT7 and 5 other receptors with way more strength than 5-HT2A & 5-HT2C are hit, this ensures a mind-manifesting trip that is the opposite of an "in your face" trip which so often occurs with many synthetic man-made psychedelics like DOC, DOI, DOM, 2-CE, etc. which way overstress 5-HT2A & 5-HT2C over anything else, this in turn can cause lack of spiritual insight, too much body load, too much and run-away stimulation in comparison to sedating tranquil qualities, difficult trips, etc.
25i-nbome recaptures the overflowing empathy and euphoric qualities of LSD to a "T", i've used it enough times to know this for sure, this quality was also found to be inherent to 25i by Erny as well, the good humor, the overflowing empathy, this is the shared mindspace between 25i and LSD, it is a trait of high 5-HT2A & 5-HTC agonism, 5-HT2A & 5-HT2C agonism is also responsible for in depth behavioral qualities along with visual presentation. Adding this into the tryptamine trip (keep tryptamine dose high so that it is not "over-ridden" with 5-HT2A/HT2C agonims from 25i, keep in balance!) at a very very low dose, should serve to accentuate the empathetic, behavioral and visual qualites of any psychedelic trip, analogous to the overflowing joy-ous empathogenic LSD trip. So keep the tryptamine dose high (or mescaline dose for that matter if being used) yet add back in "just a touch of love" from the 25i with a very very low dose.