Bill--A long time ago (1977) I bought Dave Platt's Waco YMF-3 when I was teaching university in Norway. Because there was no place around to fly it from landing gear (but lots of lakes and fiords), I decided to put it on floats. I flew down to London to some show or conference that hosted models and bought a set of floats designed for a 60's powered Supermarine racer. Sorry to say I don't remember which company, but the floats were two-piece glue-together fiberglass and in appearance fit the model perfectly. The Dave Platt Waco has a 60" wingspan, and I would like to fit it with a Saito 90 radial (it's about 60% complete after forty years) . But by the time I add in the weight of the floats, radio gear and aerial video for AV flying, I'm guessing the weight will be around yours, and I'm uncertain whether the scale floats I fitted have enough bouyancy. I have been debating between Saito's 90 radial swinging a 13" prop, and their FSR 170, which can swing a 16" scale prop. But I don't know if the Waco designed for a 60 will handle something that large, probably three pounds more than the recommended 60, though I've heard biplanes are notoriously tail heavy and have to have extra weight up front. I'm assuming your 1/5 scale Waco has a 60" wingspan, same as mine. What are you using for a powerplant? Unfortunately I'm sitting over here in Norway for the moment (until April 15) and the plane is at my home outside Salem, Oregon, or I would mail you the dimensions of the floats. When I get back I plan to put the model in my pond, load it with all the weight I think I need to finish it, and see if the existing scale Supermarine floats are adequate. Would very much like to hear from you on your proposed powerplant. Dick