You would want to get the very smallest AG pump/filter combo you can find, something that uses AT MOST a 3/4 hp up-rated pump, not full-rated. 1/2 hp would be better. I can't find company specs on it but Hayward makes a small sand filter pump combo called the VL40T32 series that's probably just the right size. It uses 42# of sand and a 1/2hp pump (probably up-rated) and flows about 30gpm. Check the web for it but it looks ideal. You may have to mess with fitting adapters, but that's not too hard.

Carl