These old " Trade Name " Crescents don't retain a great deal of value. They were sold in hardware stores for the every day man to put food on the table and keep the fox out of the hen house. I have seen them go a gun shows ( in good condition ) for 100 to 150. I saw one go that was in bea-tee-full shape for 200. In the condition that most of these old shot guns survived, in well used condition, I would venture the lower value. As for the circles stamp ( actually it looks like four circles, one is worn away ), many of the odd markings on old American long arms were made by long gone and unknown workers, doing unknown inspections and assembly in a long gone factory. In other words I don't have a clue, it could mean something or nothing. I would guess it means something only to the people on the assembly line at the time.