If you hop over to Cancun (not very far from Cozamel), on Tulum road, right downtown, there is a vet supply place there. Not sure the name, but that's supposed to be the best one in Cancun, anyway. The pharmacias there all had clen, sust (very weak redijects, not cheap), clomid, sten, and deca. The gear in the pharmacias seemed pretty expensive for as weak of doses they were. I think in resort towns like that they really stick it to the tourists. good luck
Hard