Dave B gave you a great list of books to review. You might add: The Kentucky Rifle . . . a True American Heritage in Picture, KRA 1967. Mostly rifles, but includes nine pistols. Has good photos both right and left sides. Glad to hear about Beebe & Bingham, started looking for a copy.
I have been looking closely at the American pistols of British holster style, to learn exactly what distinguishes American from a common English pistol. My incentive is I am in process of purchasing such an American pistol. Walnut stock, woodwork not up to English standards and a truly squirrely little thumbpiece.
Flayderman’s Guide to Antique American Firearms, under the section “American Colonial and Revolutionary War Firearms, subheading Pistols” says:
“Two general styles have been noted (a) Those closely patterned after the British holster pistols of the period, often distinguishable by the type of materials used, such as the different wood and very often the lesser quality of workmanship, and (b) The so-called “Kentucky” type . . .Although distinctly American in appearance the earliest specimens retained very Germanic characteristics.”
Sounds like you have two basic styles to consider. Being individually made, the characteristics tend to blend into each other in some guns.
American holster pistols of the English style are shown in:
Battle Weapons of the American Revolution, George C. Neumann. Page 270, American Holster Pistol Circa 1740 – 1760.
The Pennsylvania – Kentucky Rifle, Henry J. Kauffman, plate 86, also pl. 88, 85
Firearms in Colonial America, M.L. Brown, page 273 American pistols with similar "cane-handle" grip style.
The Kentucky Rifle, Merrill Lindsay, photos by Bruce Pendleton, section 20 Kentucky Pistols, walnut stocked pair by Switzer, Lancaster, Pennsylvania, same grip style ". . .could be either British or European, but the pistols are very much American in the shape and treatment of the walnut stocks." The same pair is shown on page 216, Kentucky Rifles & Pistols 1750 –1850, James Johnston.
The New England Gun, Merrill Lindsay, illustrates a pistol by Asa Waters, No. 32, with grip, and thumbpiece very roughly similar to what I am getting, and some silver wire inlay.
These holster pistols, English or American, were generally smooth bored, no sights.
For shooting I am currently assembling parts to make an early Kentucky style pistol, .40 cal 13/16” octagonal barrel, roughly like the bottom pistol on p13 of Sam Dyke’s book, but using Schroyer style tang carving & sideplate.
