Thanks, everyone.
I did email Joyce Chen headquarters and they said that it was out of stock for good.
Someone linked to some similar ones. Those are pretty but they don't have the earthy "matte" appearance of the Joyce Chen ones. Thanks though.
I will keep checking Ebay. I just can't believe that they are so hard to find. Usually one can find anything on the internet if they look hard enough but this teacup set seems impossible to find.
If anyone has a complete set that they want to sell, I will pay 200% of the original price.