Rear Wheel Bearing Replacement Seals

Hello RS25,

I'm looking to replace my rear wheel bearing on my 97 OBS, but I can't find the part numbers for the seals anywhere. I've googled all night, and searched RS25, but nothing.

Is this something I must replace when doing the rear wheel bearings?

I found this, but what is 5,12, and 13?
http://opposedforces.com/parts/impre...llustration_1/

Thanks,
- Someone with loud "whums" and "popping" from the rear.