I can't say for certain about your specific sight but most rifles of similar design use a small press (some European rifles include it in a tool compartment in the butt of the rifle) that ensures it gets pushed in and out straight. I suppose you could use a properly sized drift punch with proper support under the barrel but I wouldn't try that for fear of peening over the end of the pin - that's just make things worse.
If I understand the question correctly, you want to remove the sight pin from the housing? The pin is spring loaded with a detent that will need to be depressed as the pin is removed.