I think you would be better off looking for plans rather than a kit. I have an old Berkly Ercoupe of about the same vintage and the wood has totally dried out and is very brittle. (The first $100 takes it). It would not build well and I feel the Sea Cat would be the same. It was one of my favorites when I was a kid. Nice lines but probably too much dihedral to make into a good R/C. It's been done though.
Good Luck.
Peter