Very unlikely you find them new, if so they’ll be new old stock.
They came in 3 different size trucks, so plenty of used ones.

There was a spindle bearing diameter change in the early 50’s may look that up and decide if you’re better off with the early or late version of the spindle.

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
---All pictures---
"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-