Yard sale find was an almost new Stith scope mount complete. From some web crawling, it's designed to be mounted on top, not like some using the peep sight holes in the receiver side.
The front part that mounts on the front of the receiver and holds the spring loaded single ring, is unmarked except for "Stith Mounts" . The part that goes on top of it, on which the scope rests is marked "M2W". The rear mount which goes on the rear of the receiver is marked "M3R2". Both front and rear mounts have a large radius contour far larger than a typical bolt action receiver.
Can't find any info on the net to decode the markings. Anyone have a chart ?
Here is one installed to show how it works.