I purchased a first generation Universal carbine. Someone filed the wings of the front sight off and cut a V in the rear peep sight. The rear sight is a milled G.I. Sight. Can and how does one take the peep slide off and can it be purchased and replaced without having to purchase another complete rear sight and sight tool? Also, does anyone know where I can find a replacement front sight? I have looked everywhere from Numrich to eBay, but I can't locate one anywhere.