With the alternate part numbers on the Filling Station offering that Dan posted, I actually found one of them at O'Reilly KC11445Y which matches the dimension shown for Timken 17887 (cone) and 17831 (cup). A little spendy actually more than what the Filling Station wants. These numbers all come back as tapered roller bearings.

I think I'd be reluctant to use a ball bearing on a differential as they don't have near as much contact area as a tapered roller bearing.

Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.