Mossberg offered three grades of Pederson SxS's. Prices in ascending order were: 2500 Grade III $275.-, 2000 Grade II
$650.-, 2000 Grade I $970.-. I believe all of the above were built by one of the Aramberri firms.
There were three grades of Pederson over & unders. Prices in ascending order were: 1500...$400.- to $420.-, 1000 Grade III...
$500.- to $525.-, 1000 Grade II...$650.- to $675.-, 1000 Custom Grade...$970.-. The Series 1000 grades I, II and custom had Beretta actions and barrels.
The 1500 series had a completely different action than the Beretta. The photo and caption in the 1974 Gun Digest Annual showed a low profile frame but, did not state the type of action ( crossbolt, underlug or Boss ). As I recall it was made in Spain but, I'm not sure if it was built by Aramberri. My early 1970's Asociacion Armera directory lists the firms of Aramberri Hermanos, SRC and Hijos de V. Aramberri y Cia, S.A. as manufacturers of SxS boxlock shotguns but, does not list either firm as making over & under shotguns. However, it appears that
a number of Eibar gunmakers purchased actions and barrels or complete guns from other firms and rolled their names onto the barrels. Francicso Sarriugarte built a decent coil spring powered sidlock O/U during the 1980's. After the Sarriugarte brothers formed Armas Keman to produce a Boss actioned O/U, the identical photos of their coil spring sidelock O/U's appeared in the Vda Hijos De J.J. Sarasqueta and AYA catalogues bearing those manufacturers' names.
BTW, if you're looking for old gun catalogues, check out the Cornell Publications website, www.cornellpubs.com
. They offer scanned and computer printed reprints of many old U.S. and European gunmakers' catalogues. They aren't factory originals but, they are decent quality, affordable and they have the same information as the originals.