What's the other side look like? The way that's peened over I'd try to push it out from the other side unless Kokomo Jr fixed that side too. That's not the pivot bolt. It's the cocking link rivet. A motorcycle chainbreaker works. If you don't think you're capable definitely send it out.
If it's working leave it alone. Don't fix what's not broken. Even if it's unsightly because you'll only be inviting the possible damage to other more important and irreplaceable parts.
someone drilled a hole in it for some reason what i would do is get this https://www.trrobb.com/Weihrauch_Quick_Detachable_cocking_arm_front_pin/p1449438_13107089.aspx now if you look at Chambers parts diagrams the HW95 and the 55 use the same rivet so the pin and clip would be a good solution not factory but better than you could get someone to clean the breech block up also