The 6.77 ct IF Clarity, D Color Diamond Solitaire Ring…only one million dollars and available online from Costco. And the nice part is they only have one so they can't expect you to buy in lots of twelve.
Also, it says "Costco.com products can be returned to any of our more than 500 Costco warehouses worldwide" but they also warn you…
When returning unique jewelry items, or items containing a 1.00 ct center diamond or larger, Costco warehouses may require additional time to verify the diamond, in which case a refund will be approved upon positive verification and as long as the item is not damaged or changed in any way (i.e. resized or reset). This process may require two to five business days.
Also, Gift Messaging is available.