Thats kind of a weird combo. When I think small rivers, I'm thinking that you will be hitting small to medium sized rocks from time to time. Maybe even sliding over rocks. Rounder more rockered "displasment" hulled boats like the jefe are great in that kinda water.
When I think surfing, Its a flat bottom "planning" hull that ya really want.
So, with that in mind, I'm thinking Jackson hero, pyranha nano or ammo.
If your idea of a small river is deep enough that you rarely will be hitting rocks. Then Jackson Fun.