Needed some real creativity to mount that AJ Parker sight (made for a No. 4 Lee Enfield) onto a small ring mauser! Not sure from pictures what modifications done to that sight, but with the attaching screws included, as shown, that rear sight seems to go $250 to $350 by itself. Marks on receiver seem to show Crown over 68, with the additional rune, so appears to be a made up by Carl Gustaf in 1968, and proofed then. But would have been 6.5x55, I believe? Not so sure about the bolt - that has been "sported" - neither the straight CG bolt, nor the curved down Husqvarna bolt. As originally made, would have had Pramm, CG, Soderin, or a couple other versions of rear aperture sights - unusual off set screw mount pattern - 3.0mm or 3.5mm , I think, and, I discovered, that almost each maker had their own pattern for the mounting holes - often not interchangeable.