Foety Miles a Day on Beans and Hay by Rickey has some good info in chapter 7 on the troops pay, purchases and spending in the Indian Wars Army. They didn’t make much and everybody was trying to get it. They did not get paid in actual money again until 1879 and the suttlers and off- post hustlers would hose them by discounting their Army scrip from it’s face values.
BTW, my WW One ammo sergeant grandfather on the Western Front said they would play cards using different kinds of ammunition for chips. They settled up in the rear later. One day he finally beat a real card shark and one $300 from the guy. The next day shark tried to run a German barrage in his truck full of ammo and got vaporized. There went the money. :-(
dang
Bummer, hate playing for chips or chip equivalents.