Sold my '51 GMC 2 ton 15 months ago........had the front end rebuilt in '98. Got the king pins from NAPA; but they only had them in "Standard", not the +.010" over size..........hope the King Pin "eye" in your axle isn't too hogged out.....
I don't see why a machine shop can't MAKE the King Pins and the bushings. All the spec's are in the manual as far as dimensions go. Probably cost prohibitive though.
Everything on these "Big Dogs" is expensive.......get used to it
One and a half and 2 ton use the same axle.........no ball bearings either. They have a rare style called a "barrel" type; no longer manufactured. Timken does make a tapered bearing set for these trucks, I paid over $400 (in '98) for one set (one side, outer bearing).
If you don't have a NAPA near you, they are online..........
Try all the links to vendors listed on this site first.........if you have no luck there, try egge.com . They go back to 1917 and some even older. They make everything in-house, just email them and ask.
Sorry about the spelling folks.......I don't type! Just hunt 'n peck........

:rolleyes: