That is an extremely nice pistol. Yes, it is a true dueling pistol with an exceptional conversion, quite possibly done by one of the Mortimers themselves but certainly of the very best London quality. I certainly hope you won't even consider altering it.
The engraving on the hammer ought to be slightly different than the rest of the gun. None of the great London makers actually engraved their own guns. They all utilized trade engravers who specialized in gun work. The pistol itself probably dates around 1800-1805 and definitely began life as a flintlock. The conversion, which is not only of the best quality, but of a form quite rare on London quality guns, dates from about 1825-1830. In the fashion conscious London trade the "flat-form" hammer was largely obsolete by 1835, so its virtually impossible that the same person engraved both the hammer and the rest of the gun. This in no way compromises it... it is exactly as it should be.
I know this pistol... in fact, I very nearly bought it myself at the Hartford show. I would have had I not been husbanding my resources to buy items to illustrate my Ketland book. I've even visited it on the net a couple of times, regretting having passed on it but the extra money for something that is out of my immediate area of concentration just hasn't been there lately. Congratulations.
