The Casino Da Vinci chips were one of the very first china clay chips, produced for DaVinci Imports by Eastony Industries on the Spirit mold (which is their corporate logo). Most are probably out of stock, as they haven't been produced in many years (so any chips you DO get will be pretty old, if breakdown due to age is a concern).
Considered by many at the time to be a lower-tier china clay chip/mold, when compared to the PGI Private Cardroom, Dunes Commemoratives, Desert Palms, and Pharaoh's Club chips of that era (which all sold for 32c-39c when new at the time). The DaVinci chips (and Pyramids Casino, also sold by DaVinci on the same mold with different stickers) were always overpriced imo.