Any stockmaker worth his salt should be able to make one. Make the base out of black ebony, enlay the gold oval, then remove oval & drill counter sinked hole (pin between grip cap & stock to keep alignment) then screw grip cap base on, then glue gold oval in place.

Thank you all for your pictures and suggestions. A lot of good info . Tracy

A grade grip cap
 

This is the one on my 1891 A grade 12 gauge.
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