As Blair pointed out, the latest model hardware ( in this case your desired Sharps Rifle) will determine your time period.
In My case, my time period sorta slid forward:
I started with 1858 NMA Remingtons
added an 1863 Sharps Papercutter Business Rifle
added a Model 1866 Yellowboy
now I am working to get the earliest shotgun I can affordable find.
Whilst this sets me nicely in ~ 1867 the shotgun ruins the time period since Currently I have an 1870-ish Belgium 12 bore double
I am building a caplock 12-bore double based on an original virtually unused damascus barrel set, which will allow me considerable flexibility - I can use it with the 1867 persona or use it in order to fit into the 1852 period with Colt 1849's and 1851's, and a Plains Rifle .
The Prof Marvel Peddlar Persona will fit into either decade with only minor clothing changes that fluctuate with fashions such as Hat, neckware, shirt, waistcoat, etc.
Prior to 1850 ( fur trade era events) I use a generic "dumb white boy who wandered into the prairie and was saved and raised by Lakotah who were amused at his songs and pitied his patheticness"
BTW Baker's pipe is a medium length briar bent of Western European or Germanic ( probably Bavarian or Black Forest) styling.
yhs
prof (pathetic) marvel