I repaired my sending unit float 2 years ago. It had a small hole in it that I was able to solder shut. It worked for almost 2 years before it began to take on gas from another small crack and cause the gas gauge to read Empty.
So, today I pulled the sending unit out of the tank and confirmed that it was filled with gas. I went to my local Ford dealership around the block. The parts man looked up the float which is the same one used on most Ford cars in the early 80's. He found the part number and located another dealership that had one in stock. So, I drove 5 miles and bought it. I paid $15 which is more than they cost, but, I had it in my grubby little hands and I did not have to wait for it to be shipped and pay shipping costs. And remember this is a dealership where everything costs more.
Got home put the float on the arm and installed the sending unit. Turned on the key and watched my gas gauge move to ½ a tank. Now I'm a happy camper.
old float on left. FORD part number COAZ-9202-Boriginal float on left....solder repair....new float on right