Greetings from Spain
Great to see a forum dedicated to this fantastic equipment. The Tandberg gear I'm mostly interested in and collect is Educational equipment (language laboratories). Not exactly run of the mill, I know! Also have a few of their 1970s reel to reels.
There are some educational equipment for sale now and then here in Sweden.
You can search on hifishark of course and I regularly search the Swedish "ebay" tradera.com.
There are actually some such cassette decks for sale there right now.