For galantamine and choline, search for the thread on it on these forums.
Basically if you're in the U.S you can buy galantamine pills legally, without prescription. I think for some reason everywhere else you need a prescription though.

Extracts are not consistent. You can buy choline pills almost anywhere.

Most people take them with WBTB to get a better effect. I think. The thread on it will have more info.

The purported best herbal supplement is Calea Zacatechichi. You can buy a seedling/cutting and grow your own plant or just buy a bag of dried leaf (which is really bitter). Fresh leaf is not bitter at all really.

There's more info on this on the main website with other supplements too.

Cannabis works for some people. If you live in a medical marijuana state/country, get one with more delta-8-tetrahydrocannabinol, Not delta-9. Delta-8 is supposed to be the one which promotes dreaming. Although it may be very hard to find info on which strains have high levels of this compound, and nigh impossible if you don't live somewhere where it's legal.