3 open ends:
1. Wels is a town in the Austrian province of Upper Austria
(Ober-Österreich). Pranz is a name not uncommon there.
Contact the municipality , they should know from when to
when this retailer has been in operation.
2. Pieper: there is also a book on Pieper, if I remember well
a contributor to this forum with the pseudonym
"canvasback" has it.
3. One photo shows a hole between the short under-rib and
the forepart-hook !!
Before you pull the trigger on this vintage
gun let it check by a PROFI GUNSMITH.
Or if you dont care , sign at least a life-insurance
contract before you pull the trigger.