Most Mk 2 were scrapped in the last 2 yrs. They dont pay to keep . VW people are cheap or buy new ones.
The current hubs can be made everywhere.
The later 88( 72/40) and up bearings last about 20hrs. The early ,smaller ones maybe 10hr. 66/35
The Mk 3 hubs, I show to be the same size as the Mk2+.
(72/40)
The Chinese hubs seem OK at the larger size. Not for Mk 1 tho. ( 64/34)
I am pretty sure that the Mk 2(66/35) small bearing can get stuffed into the Mk 1 carrier with some machine love.
The only reason to use the Mk 3 stuff is the larger brakes. as the hubs/bearing are the same,IMHO
The forged carriers dont really go bad IMHO. They will take about 8-10 bearing swaps and still have some squeeze. Red loctite keeps them snug . They can get bent steering arms in a shunt and bent in the upper strut mount area,requiring more slots.
I have never seen, nor heard of, a carrier broken, just bent.
The hubs all will break eventually at race loads with big stickys.