The rear brake isn't releasing properly on my NSR250. Since I've had this experience before on my older Hondas on the front, I figure it's simply the O ring (or O rings) that go around the piston. On the online parts page, it appears there are 2 o-rings but they have different reference numbers, and also the description is incorrect for both of those numbers. It looks like #14, "seal piston" (part number 43209-371-006) would be the correct item. but alas under 8N it doesn't even show a 1 let alone 2 as in the photo.

Whew....

Basically, do I have the correct part number for my NSR250R8N and do I need one or two? And where do I get them, local Honda shop or somewhere online? A search shows that part number coming up as a seal for all kinds of other bikes and my luck isn't normally that good. Any other advice before I get wrist deep in this rear caliper rebuild?

Thanks,
Craig