missing patio door lock

There are two locks that come to mind. Look at our 82-229 and 82-244 and see if either of these can match. Make sure that all the dimensions line up before you make a decision.

I see what you're saying. Fortunately, the hole center spacing on the 82-227 does match up to your own hole spacing, so that's a good choice. The total height, to be honest, isn't really that important, as long as the hole spacing is the same.

My main concern is the depth of the cut-out. The plate on the 82-227 is only 1/8" thick, while the cut out you show in the photo looks deeper. That's why I thought maybe one of the other two could work, namely the 82-229 which also has a 5-1/4" hole spacing. Can you confirm? I'm wondering if your original lock had a really thick plate, or if there's something else at play. What type of keeper do you have for this door? If possible, I would like to see that, as well.