The phone # on the Ernie Willson chip corresponds to a mail order & retail store here in Orange County (California) -- The Poker Store. See:
http://www.pokerstore.com/

Willson may be the owner or manager (?)

If you explore their website, you'll see that what they call the "Aztec" mold is what we call the "Large Greek Key". Looks like they distribute hot-stamped AND even center-inlay LargeKey mold chips.

I'm only about 1/2 hour from the location, but have never been in there. I'll make a trip in the next week and see what I can find out.