I have a Marlin 60 here and was going to switch out the scope on it with another similar one but which has a higher power/variable zoom. As I was pondering this I became confused at the scope mount and whether this would even be possible. I can't even figure out how they got the first scope in there. I attached some pictures, will I just have to buy some traditional scope rings? The top scope is obviously the one I want to put on, the second picture is a closeup of the weird scope mount. Can anyone tell me if this was the scope that would have come with the rifle in the 70's? Does this add any significant value?