"Sam Chance" by Benjamin Capps.
If it's the one I read years ago I really enjoyed it. Spans the buffaloe hunting era to the arrival of the automobile.
I'm ordering a copy today.

OZ

Louis L'Amour. My favorite is The Cherokee Trail, featuring (unusually for Westerns) a female main protagonist. She is not portrayed as weak or a "damsel in distress." Another "thinking outside the box" one is Down the Long Hills, with a boy about 11 years old. Others include, but are not limited to: Flint, Conagher and the various Sackett family sagas.

Elmore Leonard. Larry McMurtry. Anything they wrote.