Revuenon 50/1.4

I took delivery today of a 50/1.4 Revuenon lens. It is in Pentax K mount. When I first saw it, I thought it might be a Rikenon. My version has eight aperture blades. The serial number is on the side and starts with the letter C. I have read that there was a version with six aperture blades, which I assume was an earlier model. What I don't know is whether it was made by Chinon or Cosina. The online reviews are mostly st least ten years old and are mixed. The reviews which were not as good are invariably from people who used the lens on non-film cameras. Some of those cameras are hard to use with manual focus lenses, especially fast ones used wide open. When the weather improves I will put the lens on a recently acquired Promaster 2500PK Super and take some pictures.