Found on eBay for the GS-F, so they do come up?
https://www.ebay.co.uk/itm/333739677140?mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338353466&toolid=20006%26customid%3Ds%3AGS%3Bgc%3ACj0KCQjwspKUBhCvARIsAB2IYutqIkt_oUJmkLmIXAB2De-nwpDIGBcAjVb__DLvHHgQ-X5oadJVyRsaAhOmEALw_wcB%3Bpt%3A1%3Bchoc%3A2&customid=s%3AGS%3Bgc%3ACj0KCQjwspKUBhCvARIsAB2IYutqIkt_oUJmkLmIXAB2De-nwpDIGBcAjVb__DLvHHgQ-X5oadJVyRsaAhOmEALw_wcB%3Bpt%3A1%3Bchoc%3A1&gclid=Cj0KCQjwspKUBhCvARIsAB2IYutqIkt_oUJmkLmIXAB2De-nwpDIGBcAjVb__DLvHHgQ-X5oadJVyRsaAhOmEALw_wcB
But there must be a separate electronic control module? Unless it works in conjunction with the front control module. To junk the whole mechanical bit for a failure in what appears to be a programming failure seems madness!