Take a look through the Fuji and Seymo pages on here (I think Aftco are sea rings). There might be one that closest matches yours.
Ever thought of getting the old bit of carbon out and re-using the existing ring? Most are only fixed on with a weak glue and we used to use a lighter to warm them up and pull the carbon//FG biit out with pliers. The diameter of the new section might then be too thick for the old ring, but they are worth keeping in case it happens again with a thinner rod.