2nd of the ten different answers.
I would only differ on the motor/ESC combo, and not really by much
I would look for a pair of "stock" 540 size motors, since speed is more important than torque, 3 pole types, from a reputable maker. This because they are likely to be better matched, also, like Rich said, they will have a better life expectancy. Some "performance" motors have their brushes offset to increase performance in one direction. It is generally accepted that on a twin screw boat, the props should turn in opposite directions, so motors that have the same performance both ways is a good idea.
For controlling two such motors in a boat, and keeping life simple, I would consider an Action P94. On the face of it not cheap, but you do get two ESCs and a mixer all built in.
Counter-intuitively, for an increase in speed, go for two blade props of the same size. Motor spins faster, the stream of water is caused to move backwards faster, then according to Newton, the boat is pushed forwards faster,