Here's a little advice. Take more pictures. The packaging may help with a few clues as to time period the set was assembled. Look at the reverse for mint marks and condition. Like Ask the seller more questions.
I went to my local gold silver store yesterday. There was a 1921 Peace dollar in the case with his selection of premium bullion. It was a lower grade but had a certificate of authenticity. I didn't ask the price and thought I got a picture while I was taking pictures of other things. I'll have to check back and ask more about it IF it's still available. Chances are high it's high priced, that case holds the premium goods.