I found the mentioned Elams listed in the CWS&S under Confederate Troops. It appears from the unit history at http://mississippiscv.org/MS_Units/1st_MS_CAV%28AW%29.htm

The company they served in, Co., G, was raised in Warren Co., Miss. I checked the 1850 Warren County census at http://www.rootsweb.com/~cenfiles/ms/warren/1850/ but could not find that surname. I do not have a 1860 census of that county.

HTH,

George