You can purchase mushroom spores (in syringes) legally, get some simple grow medium, pack it in glass cans, sterilize that in oven, inject the medium with spores, and grow those mushrooms in a converted fish tank (they needs humidity). Takes about 2 weeks.

Spores do not contain psilocybin.

Here is one seller: http://www.thehawkseye.com/ that I remember.