No photos of the proofs, but has Nitro Proved on the barrels
On the barrel lug that attaches to the action there are some oak leave stamps, 11 59 20/70/2 3/4"
On the barrels
J.P. Sauer & Sohn
Made in W. Germany
Hard to read, but it looks like "Frezial Fauhstahl" 20/70/2 3/4"