It's a pretty big boat for a 7 cell motor...., the 700 motor 12-14 cells is a good suggestion.

Keeping it cheap, would be a 600 Race, our smaller (20 inch) monohulls run about 20-22 MpH on seven cells, using this motor, as your boat is light, maybe it's worth a try.

With brushless the sky is the limit ( better said, the handling capacities of the hull is the limit...).

Regards, Jan.