Hi all. I bought a Beretta 75 at a gun show. I took it to the range and was surprised how off the sights were. A fellow Beretta lover at the range looked at the gun for me and said someone filed down the front sight for some reason. Problem is the front sight is fixed/integral to the barrel. Is this sight replaceable? How would a gunsmith fix this? Thanks for any help. I've attached a picture of a normal Beretta 75 (not mine).