Almost all authentic reproductions have this same problem and shoot high. Believe me, I've researched this to the ends of the Earth. I'm still wondering and waiting for clarification from "mykeal's" comment.
Shooting high I understand. Shooting right, I don't. Shooting from a rest or?
I got a used Pietta "58 New Army" a few years ago and was less than impressed. Same problem, shot high. Didn't really care about modifying it as it was used and not a serious "keeper". Had my good friend and gunsmith make a new taller front sight for me. After a couple of attempts, we discovered the flat on the top of hex barrel was tilted slightly to the left. (A common problem with the Pietta's). After this discovery, he made me another front sight only this time, the bottom of it was milled at an angle to compensate for the improper barrel assembly/angle (factory milling) (yet another well known Pietta problem) and it worked! The next issue we had was keeping the front sight on the pistol without dove-tailing it. Long story short, I used "Gorilla" brand epoxy and it's still there.
I might consider "adding" height to the front sight of my Walker and epoxy it to the existing blade rather than doing a serious mod to it. Why not!
Your comment was greatly appreciated!