I always wondered what the licensed by Starr SA meant on some boomboxes, they must have been using this mech for a long time even Tanashin was using it. Billboard 1974
Found this transport on Amazon.jp, oddly the store for the brand is dishware. https://www.amazon.co.jp/VINTORKY-テ...けの動き-カセットデッキの仕組み/dp/B0CNYB8VZ5#productDetails
These come from China with a Tanashin Part Number, I wonder if that's where people get the connection? I don't remember a new dual deck. https://www.ebay.com/itm/389440391518 New TN-21 Movement TN21 Dual Card Cassette Deck Tape Recorder Repeater
This is interesting but I don't know if it went to market From HiFi Stereophonie 1981, Luxman came out with a transport that pulled the tape out of the shell to play it. Obviously this looks like something straight out of the prototype lab at this point.
Off some shipping info website, there might be more data behind the paywall. Tanashin was shipping something to Fujitsu Ten in the USA, I doubt it was random parts, more like a finished product? Fujitsu Ten (General) was known here more for car stereos than anything else but they had a ton of products in other markets.