Many of these shops aren’t business so much as a labor of love/personal church. So you go in and obviously they try to convert you to their way of thinking
On the contrary I feel like the author came in with an easy request. He wasn't looking for anything rare or expensive or special. He was looking for world stamps. Show him world stamps you're willing to sell him.
That being said, the author did walk into the shop with a rather difficult request. How do you recreate something personal?