Adding to my previous remarks where I pointed out how inexpensive any Leica, M or screw mount, is when amortized over lifetime, I would like to add comment about Canon clones. While I have and use IIIas, C and F, I must add that the Canon clones are superior with regard to build quality.
Likewise, a Contax IIa has very robust construction and normal to 90mm lenses are reasonably priced. Unfortunately, wide angle lenses are in the domain of collectors and are relatively expensive.
Canon P is often my bad weather camera, but larger than earlier Leica screw mounts and clones.
Of course, if only a standard lens is needed consider a Contessa or Retina. The Contessa is the tougher camera. The Retina takes accessory lenses but they are awkward to use in practice.
Keep in mind all other manufacturers stopped rf cameras with interchangeable lenses when Leitz introduced M3.