I would also recommend Ralphs. I have bought a few machines from them, and every time I went there for a machine, the head dude (I don't remember his name, but it wasn't Ralph), was more than happy to show me a bunch of the kind I was looking for and test them out. Hopefully they have you part, but if they don't, and no one else does, they do have a full machine shop on site that can manufacture just about anything.
Chuck