the bearing - seal sets are fairly inexpensive. The common wisdom says if you remove the bearings you throw them away. The removal process means you have to side load the balls in the races while driving them out likely deforming one or both.
all balls set ebay
From mikes XS
Rear Wheel Bearing Kit
Rear Wheel Bearing Kit Photo Rear Wheel Bearing Kit
Includes: (1)Rear Wheel Bearing - 6304 2RS Nachi ball bearing (with 2 synthetic shields), (1) Rear Wheel Bearing - 6305 2RS Nachi ball bearing (with 2 synthetic shields), (1) Rear wheel Oil Seal - (SO-27-52-5), (1) Rear wheel Oil Seal - (SD-35-62-9)
Made in Japan - Highest Quality - make sure any you are comparing are made in Japan and same quality
Fits: All 650's, XS1, XS2, XS650 75-83, TX650 74
Part #28-6307 $46.00 USD Kit
I would guess you can take the part numbers from mikes to your local bearing house and get a seal. Those look like the universal numbers to me.