I recently bought a used Sigma Super-wide II 24/2.8 AF K-mount lens. It was advertised as "excellent" but the feel of the focus movement seemed rough to me. I chose to have it repaired since overall the lens looked good and the few shots I have taken with it showed no obvious problems. I sent it to Sigma for service, but they returned it because they no longer have parts. I tried CRIS hoping they could fix it. They too returned it for lack of parts, but did tell me that the rear seal is missing. Now that I know what to look for the missing seal is obvious. I am no expert but I assume that the lens will deteriorate as dirt gets in where the seal is missing. My guess is that it already needs a cleaning since it has probably been like this for a while.
My post here is to ask if anyone has any suggestion of a repair shop that may have access to old Sigma parts and be able to cobble together a solution. It is obviously not a very valuable lens but I'd rather fix it than toss it, I would not sell it on knowing what I know now, and if it can be fixed it will fill in a gap in the Pentax prime lineup. Thanks for any suggestions.