It's an ARF and carried by Hobby People.
[link=http://www.hobbypeople.net/gallery/127580.asp]Sea Monster[/link]

Of your engines, I'd use the Tower .46. I have been flying models since 1950, but only took up sea planes about 2 years ago. My first was a Fazer on floats powered by a Tower .46. Some people complain that Towers don't shut down. My old one always did after a 30 second wind down, but what the heck, it probably won't quit out on the lake. It never has had to be picked up. Can't say that for the other engines, 2-stroke and 4-stroke. I use on-board glow on all of them except the old, beat up, well-used Tower .46.