www.fmadirect.com, or your LHS. I think they're coming out with a new version of the co-pilot with more features, as well as doubtlessly a higher price.
I have mine on a plane that has separate aileron servos. The co pilot is designed to work with a single servo that controls both ailerons. But, I did some experimenting and found out it will work if you just run one aileron servo through the co-pilot. roll recovery is probably a little slower, but it still works fine. Being able to turn it off in flight is also a tremendous advantage.
Randy