Well, according to an article in True West magazine.
Passenger train travel during the 1880s generally cost two or three cents per mile. Transcontinental (New York to San Francisco) ticket rates as of June 1870 were $136 for first class in a Pullman sleeping car, $110 for second class and $65 for third, or “emigrant,” class seats on a bench. Jun 25, 2018
It's approximately 1,800 miles from Cheyenne to Philadelphia. Maybe more expensive that transcontinental prices?
1800 x .03 = $54 and 1800 x .02 = $36.
Just a really rough guess. Maybe around $36-$40 for the seats on a bench?
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