Old hipster,
It is hard to get genuine peyote no a days because it is so rare only the north American Indians grow it for religious use, and most of the wild growing stuff is very hard to find.
You can however trip on natural mescaline from the San Pedro (Peruvian the most potent).
Click on this site for the more comprehensive info:
http://www.erowid.org/psychoactives/psychoactives.shtml
PRIMARY PLANT SOURCES
Peyote (Lophophora spp.) San Pedro & Peruvian Torch (Trichocereus spp.)