Puzzle postcards of different states and cities.
I remember seeing some years ago in the Nashville area and at a truck stop in Minnesota.
They used to make them several years ago, even the post office designed some for Christmas and the different states too I believe. But it has been many years since I have seen any. Maybe try on-line shops like eBay. You will probably have to pay a lot for them though.
Saw a bunch on ebay sell for cheap this week