I got this info about a year ago.
I think we got a rough idea of the changeover date but I forgot to add it. David might have it.
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I finally talked to Fred at GPI.
He has been with Bud Joes for over 25 years.

I hope I can write what he gave me.

The coin inlays are stamped from .050 and .053 inch thick Stainless Steel strips about 1 and 1/16 inch wide.
The older ones with the Concentric Circles were put in a press and polished with a wool buffer. This was done one chip at a time.
They no longer use this process. Fred was not sure what year the changeover was.

The newer process: They put the inlays in a vibrating bowl with what they call “media” pellets (stainless stele pellets) and a strong liquid soap & water. The bowl polishes them.

GPI says they will now only make reorders of the coin inlays. No new orders.