I think the rise in Medium Format prices are a bit generalised.
Thanks to brexit exchange and some strange periodical price drop, I was able to snatch a small stash of film very cheap from UK (Jersey) big online retailer.
Mamiya 6/7 and Hassies have caché, the Pentax 67 and its 105mm seem to have a surge of interest.
Agreed! Probably it is down to this as well.
In my case, I was browsing Fuji GA645 prices and a year or so ago good units could be had for 350€, now the average seems to have risen to 400-450€.