I have the Anniversary cub, the one that you can get the short wing kit for, and currently have a Saito 100 on it. Yes, it will hover. I want to use the 100 in a different plane and wonder what to replace it with. I have an OS 52, will that be enough?

Probably - at least for scale-like flight. Twice I had a SIG Clipped Wing Cub with a .40 4-stroke, and they had pretty much unlimited vertical with full throttle.

Is it the 1/6 scale version?
I fly my Sig 1/6 scale full wing version with an OS .30 four stroke, and hardly use above half throttle.
Only use full throttle for takeoff and initial climb.