I made a Pontoon boat years ago using a couple external fuel tanks from an aircraft, some spare parts from the spares stash and some styrene stock. Later I made a canvas top and framework but it was damaged during a move.
This one was modeled after the one my grand parents owned which was made by Kayot. there were no seats, we used lawn chairs. Eventually my grandpa added a more permanent seat for the driver, a lawn tractor seat mounted to a pedestal. He also added storage compartments on the rear lip of the deck outside of the sidewalls to stow all of our gear as well as to hide the gas tank.
For a 1:87/HO scale you could make the pontoons from ink pen barrels. Pointy at one end, flat at the back…use two of the same.
If you can use basswood rather than balsa, sealing and filling the grain will be easier. Balsa is used for flying model airplanes because of its light weight- for any other application basswood (tight, fine grain) is a better chose.
I didn’t realize you were working in such a small scale. Indeed aftermarket wheels may not be available in that small scale- I think taking wheels from an old Hot Wheels car is indeed the way to go.
