Need Help! Matched angular contact bearings

I'm looking for another matched pair of angular contact bearings.

I was able to find a pair of matched NSK's and they allowed me to get the total error on the X axis of my mill down to 0.0003", and I'm happy with that goal was < 0.001"

Now I need another set for another axis and found these old stock on ebay. They appear to be a matched set (same box), but I'm not sure they might just be two unmatched. I asked the seller and he has no clue. I tried to find details online but no luck.

Does anyone have any insight?

https://www.ebay.ca/itm/296398607476


This is a companion discussion topic for the original entry at https://www.cnczone.com/forums/linear-and-rotary-motion/470486-matched-angular-contact-bearings-new-post.html