I have only seen two appraisals of postcards on Antiques Roadshow, and found a third appraisal today. They have done a lot of Halloween cards before and a lot of cards that included a mauve Santa and Cracker Jack Bears. When you click on the link below, you can see an appraisal for 60-65 postcards of medal winners from the 1908 Olympics, which were in London.
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