I had hope that the key might be in the stamp. I asked the seller (BK Discounts) before the end of the sale if they had any idea of the history of this set but there was no response. I had two people look at them and I got one, "Sales Samples" and one "Prototype" answer but niether of them have the expertise that you or Don have. So I thought I might post them here. Have you seen this TR King stamp before?