Hi!
The Stoeger Arms Corporation catalog Shooters Bible for 1960 Edition lists the JP Sauer # 60 side by side shotguns with two models listed as the Model 60 and the model 60 Deluxe
Model 60 priced at $ 158.00 in 12, 16 & 20 gauge all with double triggers, extractors and game scene engraving.
The 12 was offered with 30" barrels M and F; same for 28 " barrels; the 26 " barrels were offered in IC and M.

The Model 60 Deluxe was offered with a non selective single trigger, automatic ejectors, game scene engraving and beaver tail forend.
The price was $ 238.00.

Weight about 6.5 lbs with 12 bore 28" barrels for both models.
The chamber length is not mentioned but since it was being sold in the American gun market I assume it has 2.75 inch chambers in all gauges. No listed shot weight that was recommended.
It appears to have a European butt stock with drop at comb of 1.75" & 2.75" at the heel.Length of pull 14.25"
Jim