I'm not suggesting any particular camera, or any particular price level.
There are many ways to acquire a cheap, fully working rangefinder.
Given the original specs,
- Reliable lightmeter
- Good build quality
- Max 1000 euro
- Good quality glass. I love good sharp and contrasty lenses.
- Fixed lens or not... doesn't matter.
the key and priority, from my viewpoint, is finding a reliable vendor, or source (friend, hobbyist) that has a well-cared for, working piece.
It's less about which camera model, and more about getting one in top condition. Even ones in top condition can fail, of course. If it makes sense to repair it, you do that. Or you find another...
I have two fixed lens RFs over 50 years old, and they both work perfectly...Konica Auto S2 and S3. These are not expensive to acquire...