I have had an even longer association with Pentax cameras than you have............

In late 1957 my father bought a second hand Asahi Pentax to take on a trip to New Zealand.  I was 12 and still happily using a Box Brownie so felt very grand to be allowed to use the Pentax occasionally.

Eventually the Pentax was given to me and I in turn gave it to my daughters.   Same camera has just returned from a trip to the USA with my granddaughters.

The biggest problem is getting the film processed and printed.

In the meantime I was married to a professional photographer and later, my second husband owned a chain of camera stores so my current film camera is a Canon EOS with all the accessories.....which has not seen the light of day for years.

If I was buying a lense from you the question I would ask would be how loose/tight are the focus and zoom rings?  Are they within normal parameters or tighter/looser than normal?