Sorry
Just realised someone asked about AK and spin. I believe he will offer it as a PT replacement bearing for general purchase, but it is not currently listed so I don't know when. It is just another non-inverted bearing - although on a forum full of people discussing which Technics just another non-inverted bearing is best...
The bearing has been discussed elsewhere - in this guise it is sapphire thrust plate and ceramic ball (the posh version)