White cubic zirconia platinum over sterling silver ring size 9

This ring is from an estate purhase, in excellent pre owned condition showing little to no signs of wear.  Charles Winston for Bella Luce. believe this ring was part of a set originally but I don’t have a band that matches and fits it. This is platinum plated over sterling silver. White cubic zirconia stones , rectangular cushion, trillion, and round. Size 9. Stamped Vietnam 925 Reasonable offers considered