It is the rear hub shaft/shock mount for a dry suspension radius arm, they are a press fit into the hub.
p/no is 2A7351 (RH one), 2A7364 (LH one).
No idea if still available, lots of stuff is NLA now.
Easier to just go find another good arm.
Disc brake CVs will fit in a drum brake hub, internal dimensions are identical... but the disc type drive flange setup is totally different. No good if keeping drum brakes, and if going to discs the drum swivel hub has no mounting lugs for the caliper..
If you just want to fit Timken tapered rollers to a drum brake setup, then yes, they will fit, no problem. The outside and inside diameters of these are the same as the ball bearings.
On a drum brake CV they fit on the drive flange, on a disc brake CV they fit on the CV itself which is much thicker (& stronger).
Timkens will way outlast the ball bearings, they have around 2x the dynamic load capacity.
_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.
