Being busy I missed an Isolette on eBay which went for the price of a couple of pints, ffs. It's my birthday next week, and, fuck it, I'm treating myself to a medium format folder. Another Isolette on eBay went way beyond my budget: it seems that a Solinar lens will attract determined bidding.
The Franka Solida is interesting, especially as some of them have a rather fast f2.8 lens. The most detailed information on this camera I've found is here.