There's a lot of confusing info about these parts out there Bob, that's for sure. I went through the same thing when I rebuilt the 1510 transmission for the Suburban, which uses the same bearing and seal for the brake shaft that AJ refers to.
Found my Motion Industries order for the 1510 parts including their house part numbers and cut and pasted them below;
MI Item #00012369 1 2
C-R 7410 OIL SEAL
MI Item #01295057 1 1
KOYO NRB B 1212 BRG
Major
"I refuse to join any club that would have me as a member." Groucho Marx
