Lock mechanism

Question

I need to replace this lock mechanism, shown in the photo. Handles are fine, it is the mechanism  itself. I am not certain, but I believe this patio door is an old Howmet door.

Tom · Accepted Answer

This is a very, very old setup. I don't think we can replace either the handle or the mortise lock. If I had to pick out any modern part that's worth considering, it would be our 82-218. I cannot guarantee that this will work, and to be honest I'm not very optimistic at all, but I don't think you'll find anything closer these days.