Compare it with the Stoeger Krags in old Shooters Bibles. Not all of them are alike, but yours looks like it could be one of the variation. Earlier Stoeger Peerless conversions used the wide Winchester style swivels (I forget the brand name) but later ones probably used lesser quality swivels like yours. Post a picture of your grip cap and I'll compare it to my Stoeger Krag. By the way, mine has a plain metal buttplate. The Neidner style was probably extra cost.