Oval sink overflow trim ring ??

[SteveC]

I have a 1960's American Standard vintage bath wall shelf sink that I'm refurbishing. My Oval overflow hole is rusted chipped and poor condition and I want to add a trim ring to help hide the rust / porcelain chip out. I CAN find an oval trim ring online - but they are all too small. My hole measures 2 7/16" wide by 1/2" high. (Items I've found are not wide enough).
Suggestions ?? Source for trim ring of larger size? Other comments ??

Otherwise the sink looks good - but the overflow hole looks like crap. Thanks All !!