Internal lock for 82-089 handle

Thanks for writing in! The internal mortise lock you have reminds me of the 82-265 Multi-Point Mortise Lock with Face Plate. To confirm that this is the correct replacement for your repairs, you'll need to carefully look over the dimensions and compare them.

There is a strong likelihood your existing keeper will not be compatible with this lock, so I also suggest taking a look at the 82-249 Sliding Glass Door Multi-Point Keeper.

Alternate image for 82-265

Alternate image for 82-249

I agree with Jasmine that the 82-265 would be our best replacement option for the assembly shown in your photo, which is commonly used with the 82-089 style handle set. You'll need to confirm that the faceplate and lock body dimensions shown in our product images match your assembly.