Kregg's book doesn't list a Purple CORTEZ chip but she does list 10 distinct colors.

Are you sure the scan you posted isn't the Lavender in Kregg's book? You have a Lavender I see on your web site. Is the one you seek darker than that?

My brown CORTEZ can look dark purple if I turn it just right in the light. Maybe you should check your brown to see if maybe that's the one you are thinking of.