Hi Chris
The case you are looking at is a brass US 57mm anti-tank gun case. Similar to the brit 6 pounder in weight & capabilities. H/S is 57mm m23a2 F.A 1943 (Frankford Arsenal)
Cheers
The building is my own private 24/7 pub!!
Was going to turn it into a machine shop but wife didn`t want collection in house so decided to turn building into boozer as we are in the sticks.
I am keeping one pump & selling the other. They are old & from a portable beer stand for doing shows etc