Texas 55,

If you are referring to the retainers that have bend-up tangs for the trunnion (?) bolts (two trunnions, each with two bolts = two retainers), Chevy Duty has them (they have the correct strength bolts, too).

(1947-54) U-Joint Bolt Lock Clips : Part # 92-222 Chevy Duty on-line catalog

Tim