Or was what is being called "Priest's regiment" actually the 10th Missouri Cavalry Regiment? I ask because I found this on some genealogy page that tells all about John W. Priest and his family history. In the relevant part it says: "He then purchased the old home farm, and engaged in farming, but in a short time sold the farm and engaged in merchandising in Emerson, Marion County, Mo. where he remained in business until the breaking out of the late war. He then left his business, and organized a company of 130 men, of which he was made captain. Mr. Priest afterward joined the Tenth Missouri Cavalry (Confederate States Army), but later changed to infantry. After serving the first six months he was made lieutenant-colonel, and three months following he was made colonel of the regiment, and was in many battles, among them being Athens, Monroe City and Shelbina, and then Lexington, Mo., where he joined Gen. Price's forces and was afterward transferred to Tennessee, or the East, and arrived at Corinth a short time after that battle. He was in general fighting for the next month, then was sent West to Arkansas Post in Parson's brigade."

http://www.mygenealogyhound.com/missouri-biographies/mo-scotland-county-biographies/john-w-priest-genealogy-scotland-county-missouri-jefferson-township.html#

Now I can't vouch for how accurate any of that is but is that saying that he was made colonel of the 10th Missouri Cavalry Regt., thus "Priest's regiment" would be the 10th Mo. Cav. Regt.?