Technical Fuel pump ID help

Afternoon Hamber's

I'm looking for some help to ID my fuel pump. I took it off to rebuild as I'm having some fueling issues, but on taking it apart I found the pump arm was twice as thick as the one supplied in the rebuild kit, and it also had a second diaphragm in the bottom half, which is unlike any pumps I've seen in tutorial videos.

The bottom half looks newer so some type of retrofit but I'm unsure?

Any help would be much appreciated.

The pump is off a 1950 Mercury running it's original flathead.

 

49-51 or 53 Merc with the vacuum pump for wipers. Many cars from the 40s-50s had the vacuum pump on them.

 

Thanks Squirrel, any idea where I can get the correct rebuild kit for it?

 

Nope, sorry