new lock and keeper for Php-28, series 870SGD, SGD-R20-96x96

I can't be absolutely certain what mortise lock you need without seeing the original, but the hole looks like the type often seen with our 82-218, so give a look at its dimensions and see if you think this could fit in the door. The 82-226 or 82-227 types with the longer faceplate might also be a possibility, but I can't say for sure. For a new thumb lever, I believe the 82-106 should work with this handle set. 

Not that the body of the mortise lock that fits into the hole will be the same as the 82-218; the 82-218 is the exact same body in the 82-226, but sans that faceplate, and it's the faceplate that is 3/4" wide. Most important to me are the hole spacing dimensions. Make sure that the center-to-center hole spacing 4-5/8". If so, I am leaning more and more towards the 82-226. Again, I can't guarantee it without seeing an original, but it's my best guess if the hole spacing checks out.