Thinking about the mast floatation agian, if you could find some of those colored round foam tubes that they sell at walmart and other stores, the ones about 4" in dia and 4 feet long for kids to play with in the pool, you could remove the mast head and stuff a couple in the mast. I would apply a little marine adhesive caulk to keep them at the top of the mast. The foam these things are made of is an ideal foam for this application, I think, and the size is just about right.

Would only work if you did not have a comptip.

Just a thought.