I had to play the same game for my car. “Name that MC”. Took me a few days to figure mine out.
I used the NAPA website. They have great pictures for the master cylinders and specs too. Yours could be from a 74 Mustang or close to it. It would be best for you to measure the piston bore on your unit to help you ID it exactly. The Mustang2 used 15/16” bore it says. Look at this unit here:
https://www.napaonline.com/en/p/NMAM2139