So I bought series 5 (2019) on playbill store. I found series 4 (2017) on eBay. There is one for sale now for less than I paid. I found the next earlier one on eBay but I think the seller just used a stock picture since the dates on the box don’t match the issue date of Series 3 (which would be around 2015). Does anyone have any suggestions of where the first three puzzles might be found? I just keep checking eBay but maybe there are other sites for puzzles.