I built one of those ages back for a Korean War display, using the Testors Texan. I can't recall what I used for the float, but the reference I had on the plane stated it was taken from the remains of a Japanese floatplane and that yes, the tiptanks from an F-80 were the tip floats. Then again, it's a single source of info, so no idea if it was accurate.
Alvis 3.1