Time to downsize! If you are interested in trying out manual focus or adding to your range, here's a cheap way to do it. I would love to sell these as a lot for $35 plus shipping, or separately. All these lenses have solid metal construction and are a pleasure to use. They are all capable of getting very nice images, on film or digital. I have tested them all recently on my K3 and they are all clean and working perfectly (except aperture on Vivitar, as noted below).
I'm attaching photos of the lenses and a sample picture taken with each. Ladder is with 50mm, pink flowers with Vivitar, and raccoon with 135mm. Also, what looks like fungus/dirt on the 135mm lens is reflections of trees overhead - glass is clean
Pentax A-50mm f/2 -- this has "A" setting (auto-aperture): $15
JC Penney 135 f2.8 -- fully manual, no "A" setting; has a nice built-in hood: $20
Vivitar 70-210 f/4.5 -- has "A" setting and also a macro function. However, its aperture is stuck wide open. I am not sure if it came this way or happened somehow when I used a Dremel (mini-sander) to reduce the size of the metal protector on the back, so it fits into digital cameras. I took a bunch of photos with it like this and didn't notice it was stuck until I removed it from the camera. It's very sharp wide open, so this did not bother me, but it may be fixable if you are handy. $10