Assumption: your axles are not bent. The splines are ok. Bearing surface is pitted or worn.
I have not seen a new manufactured axle from my experience. Finding NOS axles may be possible, but I have not run across any in my search.
You can recondition the original axles by having them machined or turned on a lathe and finding a bushing that is heated and slipped on the turned segment where the bearings ride.
Some have done that here and located a new bearing set to fit the bushing and hub. I can’t recall if it would be an undersized or oversized bearing. A careful search here may yield that discussion or some may chime in.
That approach may be your best bet if your axles need it.
Last edited by tom moore; 12/14/2020 1:33 AM.