Hi Gino,
Lets put it this way,
If a 6202 wears out with whatever load it is subjected to it within 6 years then it can be replaced around 8 times for the cost of the so-called OEM rear roller bearing.
So in the end who's laughing, the reduction collar can be used over and over again and honestly the new modern well made bearings will outlast the battle-weary old ones that have done well over 30 years of service.
If you are to make a a small amount of collars and keep them on hand I'm sure we can wing some business your way as we get asked about this situation quite regularly and thus you can sell the collars on their own or as a package deal with the bearings. One way or the other it might end up putting some serious pressure on the two eBay guys to stop being so greedy and level out their pricing structure some what.
Competition is always good for the consumer.
Cheers,
BB.