peter:
This is a thread which I shall enjoy following! As you know, I love nothing more than restoring these old boomers, and returning them to the hunting field. You have a challenge ahead to be sure, but if you can bring the metal up anything like the stock, then it will be well worth it in the long run. Much more personal satisfaction than simply swapping heaps of money for a bright shiny gun!

If you require a detailed photo of an original AH front sight, I would be happy to oblige, although mine lacks a moon sight.

You have a rare chambering there too. Have you seen Frank Findlow's article on the 20-bore/.577 in the DGJ a couple of years ago? Worth reading. Also, I think he would enjoy hearing about your AH, as he still takes a keen interest in the chambering.

A10ACN:
I'm sure you know what you have seen, but I seriously doubt that Alexander Henry would have made a 2-piece pistol grip as you describe. Firstly, there is no need to do this, as every (other) double rifle butt-stock in history is made one-piece, and secondly, if Henry had done this there is no way you would be able to see it! I suspect you have witnessed a more-or-less poorly repaired break. The toe was prone to crack on these rifles on account of the need for straight grain through the wrist, and weakening of the pistol-grip by fitting Henry's typically over-sized trap grip-cap.