Multi point mortise latch and lever

I thought this might be our 82-238 at first, but then I noted that the slot that takes your thumb lever is flat, while the same slot on our 82-238 is square. Our part unfortunately will not work.

If I remember, your mortise is an older style that isn't made anymore. We won't be able to supply anything with the same flat slot in this style. I wonder if you could still use our 82-238 as long as you replace the handle with it. To confirm, can you show me a photo of your existing handle set?

I've never come across this handle set before. Like Tom said, your old mortise looks very much like our 82-238 but it probably won't work with what you have here. Your only other option would be to purchase both the 82-238 and 82-080 handle set and see if you can get that handle set to install on the door, but there's no guarantee that it will. Check the mounting holes on the handle with yours are the same distance apart at 4-15/16". Also check to confirm that our mortise 82-238 dimensions match yours.