I only ask, because there are many inexpensive 50mm lenses. For example, you could buy a Praktica LTL or MTL, probably for $30-$60, and get a good 50mm lens. Plus, the LTL and MTL bodies are very good cameras. Not state-of-the-art, but good, practical cameras ... "Praktica"l.
The earlier Praktica FX models often have a Biotar or Tessar, but those often need to be rehabbed. Same goes for the even-earlier Contax and Pentacon models. Plus, these have manual or semi-automatic apertures (you have to reopen the aperture after each shot). These use lightweight alloy mounts (aluminum barrels).
As well, the Vivitar XC-3 camera often will have a f/1.7-2.1 50mm lens attached that is very good. These often sell for $20 or less. There are f/2.8 versions, but I'm not sure if these are Planar or Tessar types.
If I was looking for a 50mm lens, I probably would go for a Praktica LTL/MTL first or a Vivitar 50mm lens.