One thing I noticed in the pictures is that the lugs are different for the front and rear wheels. It appears the front wheels are 10-bolt, and the rears have the open-center wheels with locking wedges holding them on. That would be VERY unusual for any kind of factory job, even a NAPCO. You'll probably have to find a heavy truck shop or parts supplier that can research the axles by the part numbers.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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