Can you easily remove the sight and post some photos? I think most of the no drill sights involved pulling the cutoff lever out. The part of the sight that inserts into the cutoff hole should be relieved so that cartridges should feed from the magazine.
I wonder if that part of the sight was modified on purpose to be a single shot? Maybe local laws required it for deer hunting?

Added thought.
That other rifle was a real eye catcher. I know everyone here would like to see yours if it is similar!
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