charlie fusari(although he did put up a hell of a fight for the vacant welterweight title against bratton)
Fusari is a fighter LaMotta would eat up. Cecil Hudson, despite being a tough journeyman, should've been a beatable opponent for LaMotta, but LaMotta messed up in a big way by putting up a half-hearted effort and losing a split decision. LaMotta was already a fighter that the title holders weren't too willing to face and a loss to a lesser opponent put him away from title contention, if not for his dive against Billy Fox.
Someone like Pavlik or Paul Williams stand decent chances, neither great, but both have the workrate and size to make it very difficult for Lamotta