You might want to pack out your cush rubbers with some bicycle inner tube. If the sprocket carrier has a lot of lateral play it will stress the bearing. Packing the cush rubbers will help to reduce the play.
Get a good quality bearing, it's an odd size (Suzuki might try to tell you that you can only get it from them), but you can get it from
www.marksman-ind.com fairly quickly and for a decent price. Get a "KOYO 62/32DDU Rubber Sealed Deep Groove Ball Bearing 32x65x17mm", that's exactly what I used when I replaced mine and it's still good after 50k miles. KOYO are a good brand despite sounding a bit dodgy, AFAIK it's a Japanese brand, correct me if I'm wrong
+1 to Diver's advice of doing all the wheel bearings while you're at it.
Rear wheel bearing are 20x47x14mm, you need 2 and I used "SKF 62042RSH Sealed Deep Groove Ball Bearing 20x47x14mm" from
www.simplybearings.co.ukFront wheel bearings are 17x40x12mm, you need 2 and I used "SKF 62032RSH Sealed Deep Groove Ball Bearing 17x40x12mm", also from Simply Bearings.
You will also need some seals, a dust seal for the sprocket carrier hub, a dust seal on the rear wheel right side and a dust seal on the front wheel right side. I don't have the part numbers to hand, but can get them if you can't find them. I called Fowlers in Bristol with the Suzuki part numbers (I don't trust them to look it up themselves) and had them send them to me. The seals will cost you about £15 + postage so get the OEM ones rather than trying to find a pattern part.
I bought sealed bearings rather than the unsealed ones Suzuki uses, The sealed ones keep all the crap out, for the little extra cost vs increased service life and less hassle it's a no brainer
ps. The info is only for the old shape Wee, not sure if it applies to the Vee or Glee (though I think the rear wheel is the same on all models.)
pps. Moved to V-Strom Specific Discussion section.