try getting a Zoeller check valve somewhere.
they are made of a cast iron body and seem to be pretty quiet...
abvout the same price as the plastic.
also something else you should do is NOT tie that pipe to any joist.
that is just transferring the sound to the woood and you will always hear it..
you ar better off to hang the pipe to the rafters with strapping and
maybe wrap the pipe with a towell or something first where you are going to put that hanger....
anything to insualte the pipe and keep it from transferring that jarring soiund into the wood.
any hangers you have on that pipe should be wrapped with a towel or rubber armaflex first then re-hung and it should keep the sound down.