The diaphragm part you want is C5AZ-12370-A, Motorcraft DD-190. Those numbers came off the box. Do not get confused by other numbers, they are incorrect. The best identification of the correct item is that it has a 5/8-18 tapped hole for either the metal tubing vacuum fitting or the later used 3/16 rubber vacuum tube. Yes, they are rare. The current "replacement" has a permanent 3/16 od tube attached where the 5/8-18 tapped hole was.
Jim