After searching all the huge chain stores in their plumbing aisles, I wound up at Crumps. The other stores only had the option of replacing the entire plumbing fixture in question (a $50+ expense). When I got to Crumps, they sold me a single grommet for less than a buck. Not overly-friendly, but friendly enough for me to save $49!
PROS: Good availability of hard-to-find parts, good prices.
CONS: Not overly-friendly.
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