There are some pharmacies outside the USA which will ship to US addresses. Genuine brand-name product packaged in sealed bubble packages, expiration dates etc - all legit, for humans.
All this stuff about horse paste, etc is meant to discourage people from demanding the proper form of the medicine. As has been posted previously, Jimmy Carter shipped millions of doses to other countries; the only reason our own pharmacies won't sell the proper product to us - and weakling, spineless doctors wont prescribe it - is because the USA is now a wholly-owned subsidiary of Pharmaco, Inc.