The Netherlands Fan Club Magazine had an article about some cards they produced. Here is a translation of the text sent to me by Harm Koopman.
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This set of nine cards was given away along with the magazine to fanclub members to celebrate the 35th anniversary of the dutch star trek fanclub ‘The Flying Dutch’ in 2019. However the last three of them, numbers 1, 6 and 7 were send with the first 2020 magazine. In total 400 sets where made. The picture on the back is the same on all cards.
Besides this member set there is also a special set with the same card fronts but with a blue border AND the back of those nine cards have a mural (which is the same as on the single cards in the base set). In total 100 sets where made and these where given away at events and conventions in The Netherlands.
One of the specials, with an image of Dutch astronaut Andre Kuipers, was released at the special 50th Anniversary of the moon landing that was held at the Space Expo, Noordwijk, The Netherlands, July 2019. It seems that an odd number of people managed to arrange an autograph of Mr. Kuipers, which made the (not by the fanclub arranged activity) a super, super rare card!
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