There are several sources on Ebay that seem to be companies that buy up surplus parts from distributors and dealerships, mostly for older models that are disappearing into the crusher. Makes sense that this business would exist. I have bought things for 15 year old vehicles that way and gotten OEM and good quality pieces. Even Chinese companies aren't going to bother making parts for fading away cars and bikes. Bearings are almost all commodities, and if you have the old one you can get a replacement from industrial suppliers without going to a car parts source.