Why are you replacing filter media? Can't you just rinse and reuse?
If you went the filter route and could place it beneath the tank, I'm a fan of Eheim 2213 and use one on my own 10gal. In my opinion, it's the best canister for the tank that you can buy for under $100.
Fluval also has a couple great filters that would work.
If you want to go cheaper, maybe consider one of the eBay SunSun filters.
However... if you don't want to go the canister route but want more flexibility for media customization and various tweaks? Consider getting an AquaClear HOB. An AC 50 or 70 would give you tons of room and a lot of ability to tweak flow.