Throw-out bearing collar

[1950chevrolet]

Hello again!!,,,i'm looking for a collar that goe's on the part of the tranny ,where the throw-out bearing rides on,,mines all chewed-up almost right down to the base,,,The tranny is a 50 1/2 ton 3 spd on the tree,,I have a collar for a Chevy tranny,,But its off a 48 4spd,,,the 48 collar won't fit tight to the tranny(spleen i think the word is)Anyway,,I hope Someone can help,,,THANX GUYS!!! Dave:-( :-( :-( :-( :-(