Square Dial 10ee front and rear spindle bearings

Hello, I have researched and found several great threads on the spindle bearings on the 10ee lathes, and I am trying to determine what exactly is in my machine. Reason being, I am preparing for a full rebuild so I would like to start gathering the pieces now to ease the pain/cost later.

Machine Information:

10ee lathe (square dial)
SN45561
August 1962 Build Date

Everything I have found shows that the front bearings on a square dial and round dial are the same with exception to class. The round dial units having ABEC5 and the square dial having ABEC-7.

Matched pair, super-precision, front Of spindle:

Closest to spindle nose: QN20212DTX7 (flanged)
Matched unit: Q20212DTX7 (non-flanged)

My question is mostly regarding the rear pair, from what I have read, the early models were equipped with a double row angular contact bearing (one bearing with two rows) and later models had a matched pair of angular contact bearings (two bearings). Does anyone know when the design change was made?

I read one thread (https://www.practicalmachinist.com/vb/monarch-lathes/wreck-update-146913/index7.html) where the machine was equipped with a pair of angular contact bearings. A suitable replacement was part number: 7210CTRDULP3

I searched the part number and it shows they are sold as a matched pair, which makes sense.
7210CTRDULP3 - NSK | Precision Ball Bearings | BDI Serbia

So I am mostly looking to verify if my square dial has the pair vs double row bearing.

Thank you

-Marco

My '59 WIAD machine had a single 7510 in the rear. I think yours does too, and the double angular contact bearings came along later. If you look at this thread:
Headstock Replacement for a 59 10EE

Post 24 shows the rear oil slinger. This is not the type used by the lathes with double angular contact bearings. If you want to verify yours, remove the pulley and spindle stop gear and you can see whether your oil slinger and rear cover is a match.

I found a NOS New Departure 7510 on Ebay. As has been posted several times in this forum, later 7510's are not the same.

You could convert to the double angular contact bearings if you can find or make the correct oil slinger/rear plate.

Thank you for the information, I will read through that post tonight. I requested a quote from Monarch, they said they have the bearing in stock, the listed it as "spindle bearing double row, R-2293" at $465.