I'm not familiar with this boat, so a few observations on general principles.
Googling it, it looks like it is fitted to use a 27MHz radio, the pictures I saw had a label on the stern saying so and the transmitter looked like a faily generic pistol grip type. If the radio in the boat is a separate item from the other components, it will hopefully have a tuning crystal fitted. If it does, that's the good news. It means that it will work with any other 2 channel transmitter, the downside there is that the new transmitter will need a pair of crystals to allow it to work with the receiver in the boat.
The alternative these days is to change out the radio parts for 2G4 equipment, which is CHEAP. Assuming that the control bits in the boat plug into the existing receiver, replacing with new is just a case of inserting the plugs into the right slots.