Hi, I have one !
Its not called an Excellent because this is the gun they were copied from ?
Its a " Bahco " Made by the wrench people from sweden circa 1900 & mentioned in the Blue Book. ( Note the price )
Its also not 5.4 mm, I think 4.4 mm , It would make I would think around 3-4 Fpe ,
I think any of these guns regardless of calibre would not make much more , I say this because even though they are pneumatic, There is no breech seal & The pumping has no mechanical advantage ?
The one I have is in very good condition ( It needs the nickel plating to the brass parts to make " Nearly " perfect for the year )
Certainly a collectible ! Possibly a museum addition for the swedes !
Anyway, Here it is, Ged.