My 1956 Powerwagon has a similar set up. The manual calls them trunion bearings. I'd say it isn't a big deal to replace, or reshim them. Mine needed seals, and if I recall we replaced wheel bearings at the time, the planetary was leaking.
If I recall correctly, they are tapered, and minor wear can be corrected by removing three bolts top & bottom, and removing shims. It IS something you'll want a manual for.