1968 c10 pinion shaft lockbolt.

[Bluegrasser]

Newcomer here, and new to restoration. Anyway, acquired a 68 C10. Not too bad in my opinion, other than has a bit of rust, always been outside.
Anyway, had a leaking rear wheel cylinder. No problem. Noticed an axle seal leaking, so I called it a day since no local auto parts had them. They came in, installed, and noticed my pinion shaft lock bolt had a bit of wear. Can not locate one. Hate to put it back in as is, probably be fine. Plans are to redo this old thing from front to back and in-between. Hate to tear things down twice.
Any thoughts on where to look for one? All my local GM restoration places say they are discontinued. Parts stores are clueless.
Thanks for any help.