The closest match I was able to locate is our 40-213 mortise lock insert. Take a look and see if this is what you're looking for.
A quick learner says:
July 29, 2021
Seems that there are a few posts with Star Die Casting Patent No. 4.578.967. From all those questions, did anyone confirm that 40-213 is the correct replacement part??? The measurements between the center of the holes for the 40-213 is stated as 6 3/4 inches. The center of my holes is 6 7/8 inches. Do you have any other part that may fit?