I noticed a little dribble of oil on the expansion chamber right below the rear brake master cylinder, at the rubber seal end.

Am I right in thinking I probably just need to replace the seal? If so where can I source one? I can find front brake rebuild kits from various places but no rear ones. Would the seal from another Honda fit? I can't remember if the cylinder is a Honda part...

Thanks!

This is the p/n for the seal kit is 43520-MB2-315
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