Xausa,
New England Custom Guns has Recknagle(?) parts and more than likely can get you a new rear sight leaf. Install new leaf and file to sightin. You can save old leaf.Be sure to remove the rod that stands the leaf up, before drifting the pin out. The rod will be held in by the little screw under the doll's head.You could gain a little on the windage by filing the original notch some.If this is enough windage, then NECG could supply a new front sight. Whether to work the front or rear sight would be a "coin toss".