not sure if this is the right size, but it's a source (I think it's for cars, and it's a front, but it may be a common part with a 1/2 ton truck, who knows. Link includes measurements, so could at least compare it to a broken one if one needs it. I realize this post started 6 years ago, but folks keep coming back to it!
https://www.ebay.com/itm/1963-1970-C...4383.l4275.c10
jcwren, sorry, no idea on the lock washer, I'd post a WTB ad on the parts board.