You'd have to check on a store-by-store basis for a local supply, as many LFSs do indeed carry it. Otherwise, it can be had online through most major suppliers.
Do your fish actually have a parasitic infection? If not, then I don't recommend using copper as a prophylaxis--even if Cupramine is the safest product on the market (by far). If you feel you must treat the fish during the quarantine period, hyposalinity is an even safer, gentler option. I usually only recommend observation during the quarantine period for most fish, though.