I've got 2 fluval 404s on my 75, they work fine. One would probably be adequate, but I got them for $85 shipped each, brand new.
A marineland C-530 would work well I think. About $210 shipped on ebay, plus it includes media. More flow as well.
Eheims other than the classics all seem very overpriced to me, not worth it when you could get an FX5 for less.
Since you don't have many fish, one canister like a fluval 405, rena XP3, eheim 2217, or marineland C-360 would be adequate. The flow won't be much (no more than 300GPH, most likely) but if you need more circulation you can add a powerhead.