I am replacing my tub with a larger shower pan. The drain for the new shower hits dead center on a floor joist. Does anyone know if a side discharge drain is available in 2" and where I might get one? I could build out the wall so that it would miss the joist but it's a small bathroom.

A shower base must slope to the drain. If you had a side outlet drain the drain would be higher then the water it was attempting to drain. You have options here. Either build out the wall or head off the joist. Good luck, Tom

I already have the shower base and I need to make this one work. I need a 2" drain that I can install so that I don't have to cut the joist completely out. I was hoping someone made a drain for shower bases that discharged out the side instead of down.

Not for a pre-formed shower base -- You're going to have to do as Speedball suggested and head off the floor joist.

I've seen side-discharge drains, but not in the US.

See prevex.com or caro.co.uk. I've tried to get one over here for my project, but they haven't been very helpful.

Don't know why there isn't a domestic equivalent.