Ken, this topic has been discussed several times since ethanol appeared at the pump. You might want to read
https://www.fordbarn.com/forum/showthread.php?t=30531
What I think of as as the "hard" neoprene floats (per Mitch's post) have been offered by Model A vendors for years, as have the "soft" neoprene gaskets. I'm no chemist, but I suspect that the floats and the gaskets have a different makeup. My "hard" float is perfect after five years. My bad experience with the neoprene gaskets is chronicled in the earlier post.
Whatever float you choose, stick with cork gaskets, and keep a spare set on hand. It's much easier to replace your gaskets every so often than to deal with neoprene gaskets that have turned to goo and run down inside your tank.
JMHO. Best of luck. Let us know what you decide.