Right now probably your best buy is going to be that Supreme eight channel that misselman listed selling at tower for thirtynine bucks. A great Rx. The Electron 6 has proven a robust replacement for it in a micro size but is gonna cost around forty five bucks and this of course does not include crystal (only use hitec crystals in hitec Rx's ,ten bucks)

I can't tell you anything about the Bergs, never used one.

I hate to bring it up but we are talking a forty sized float plane here, if I read correctly and you bought your radio system complete as a park flyer system so that brings up the question of what servo's are you using? They also may be very inappropriate.

John