There are a Johnson Sharp and William Sharp in Clarkson's Battalion. Unfortunately no ages are given.
Johnson Sharp mustered in from May 1, 1862 at Van Buren. He's on a Sept 14th roll at Tahlequah and an Oct 31st roll.
William enrolled Feb 1st at "Derasa" or at Ozark, AR. He was on the roll at Tahlequah on Sept 14, 1862. It appears he was captured at Locust Grove on July 3rd, sent to Ft Leavenworth, then to Camp Douglas, exchanged at Vicksburg, and back to Tahlequah by Sept 14th.
There is also an Andrew J. Sharp in Clarkson's Battalion, enrolled at Natural Dam AR, that was in the same company as Johnson (Winfrey's Co.) but then transferred to co. D and was promoted to sergent.