Have you ruled out the current modern GF670 dual-format folder?

Not quite as lightweight or compact as the vintage models. But in return one gets an in-production, supported camera where everything works correctly right out of the box, and can be expected to continue that way down the road. It has a sharp modern lens, beautiful viewfinder, excellent meter, and the rangefinder is a joy to use. And those two formats, for when the other one just feels better.