Replacement Mortise Lock

While I can't say for certain without seeing the original mortise lock, the hole looks like the type commonly seen with the 82-218. The video below shows how to install this lock.

I don't know what you other locks you used, so I can't say if the 82-218 has less width. Keep in mind though that this lock has to be inserted at an angle during installation; it is indeed meant to be a snug fit. At any rate, based on the hole in your door I think this style lock is likely what you'd need. 

Hello again. Sorry to hear the 82-218 isn't working out. Let's circle back a bit here to see if we can figure this out.

• First, let's just be absolutely sure the 82-218 isn't correct. Did you try installing it at an angle, as the video I posted earlier shows? Again, it is supposed to be a very snug fit. See the video again below for details. 
• If it's indeed just too big to fit the mortise hole, let's try something else. Can you tell me the distance between the center of each mounting hole for the mortise lock, or those little holes on top and beneath the hole the mortise is supposed to fit into? Is it 3-11/16" or something else?
• Can you tell me the distance between the center of all the mounting holes for a handle set on the inside and outside of the door? And is there any old hardware for the handle set at all laying around?

Great! I thought that might have been the case, but it was best to be sure. Glad you could get this sorted. Let us know if you need anything else.