A few questions.

[Dean Romig]

It sounds like a worthy project Paul. The first thing you need to do is NOT take somebody else's word for the barrel wall thickness. With the chambers lengthened you need to pay close attention to the thickness at the foreward end of the chambers where the cones begin.
The first name that comes to mind for reengraving and re-case coloring is Doug Turnbull. He's not cheap but the work from his shop is excellent and he can do anything you want in the way of a forend and perfect checkering. They are a full-service shop.