Ken,
Was there a courthouse pre-Civil War for the Chickasaw?
As I Understand it yes, R.L. Cochran abt 1845-build a council-court log structure for the Choctaw up near Stonewall on the Leavenworth road from his house,likely rebuild after the Civil War on the same location, he was paid something like $30 per month--also next to the juction of Ft Arbuckle -Leavenworth road on map.
In 1855 land deal with Choctaw and Chickasaw there should been no need build another courthouse.