I'm not sure there's anything in the seeds.
Wherever you live, Smarcraft, you can't be more than a bus ride away from an opium poppy patch at this time of year. A swift slit to check you're not unlucky enough to chance upon the genetically modified variety, pick off the pods and take home. Basic addict activity to insure against the junkless times. It grows, no need to go online. Each pod has a thousand seeds for free, choose your best.
100 heads in a slow stewing tea will take care of any rattle and you'll feel the warmth through a 40mg-methadone-a-day tolerance. And that's if it's impractical to try to extract the opium. Nature is your friend, enjoy its bounty.