Like Mumbles said, it should be an MD-42B and here is the kit (at the site, scroll down a bit and it says it fits MD-42):
If the seal-coating is bad on the float, you will have to replace or recoat it. Can recoat with superglue, or clear hot fuel proof model airplane “Dope”. Some guys have had problems getting the DOpe to adhere well, but it has worked OK for me. If you call discount marine, they may have a float for it.
Dave
