Pentax A-50 f/1.7 (it looks like).

On LCEGroup's website. Listed as a F-50mm 1.7 but looks like an A. Regardless, is priced reasonably, and from my experience LCE are relatively conservative with their grading.

https://www.lcegroup.co.uk/Used/Pentax-50mm-F/1.7_256369.html

I think thy mean f no is 1.7, not that it an F series lens. It is an A lens and looks reasonably priced.

Of course. Duh, silly me! Agreed on pricing aspect!