I stopped at the local John Deere dealership the other day as I knew several of their critters used the Zenith T4UC carb and spent a bit of time with one of the parts guys. They are 720 and 730 series tractors. The gasket set is RE528699 and that pesky little thin tube that goes through the body into the float bowl that seems to get broken so easily is AR13009.
Not that I have anything against Cat but it just seemed there were more John Deere dealerships than Cat. .plus the JD dealer is 48 miles closer than Cat.