That's what I meant by "equivalent"- Thanks! I just confirmed that is the correct # for the 15/16 PDB master (didn't specify in the listing, only the year range), and not the 1 1/32 bore.
Being NOS, I worry about the rubber seals and O rings being dried out after 50 years, but I kinda got little choice. Decent price, though. Bought them both, but I'm going to leave this thread open in case there's more info to be gleaned out there- if that's okay with the mods. @toolmanmike ? (or maybe remove the "Wanted" banner and shift it over to the brakes section?)