only thing is you may require a different sized deck belt to maintain the correct belt tension but thats about it as far as i know.
you usually dont have any issues with compatibility unless you try to switch from PTO to manual deck cable engagement decks, i dont think trying anything like that will work
if you find an ariens, poulan, or craftsman 48" deck, look close for if the mounting brackets match then any of those decks will work as well since they are all made by AYP and most share the same exact parts