^ Loperamide! I second that suggestion. Probably I should just suggest the search engine, but here's my $0.02:
I don't know if I would jump straight to 50 or 100 mg (well, actually I do know, but I wouldn't suggest that anyone else do it). If you take enough lope, you will probably be able to halt most if not all of the withdrawal symptoms (most people who've tried it, myself included, reach that conclusion). Constipation is a genuine medical worry, so I would suggest being careful not to take more than necessary. And beware, most people feel it takes at least 3-4 hours to achieve full effect, so be cautious about repeat dosing (research I've seen online reports similar, but I can't remember exact time period).
Eventually, you will have to come off of loperamide, and it WILL result in withdrawal as well if you are on high doses (longer than heroin, but milder; people seem to find tapering off lope easier, since it's not psychologically rewarding like the centrally active opioids).
Also, in my experience, taking Suboxone soon after high-dose loperamide can lead to precipitated withdrawal (but not as unpleasant as the heroin- or methadone-to-suboxone precip wds).
Cheapest is at big box clubs (or internet), where a few hundred cost a few dollars. I'm trying not to source, and you might not b able to PM yet, but if you choose this option you can comparison shop online before hitting stores.