When I worked the parts counter at the marine retailer, we made people bring in their old fuel pumps because there were so many different versions for any given engine. Sometimes the inlets were on one side and sometimes they were on the opposite side.

What I would do is go to a real auto parts store like NAPA and ask to see their fuel pump books and start looking at the different ones for your engine. Trouble is, whenever you inherit someone elses handiwork, you never know where they found some of those parts, or what years/models they used.

I bet a few minutes looking at the books will turn up something close.

Don