You originally said you were looking for a Camp Stevens in 1864. A Camp Stevens in 1863 may or may not have been the same camp. Do you have any kind of corroboration that the unit you're looking for was there in July '64? I don't want to rain on your parade, but there could have been several Camp Stevens in Louisiana during the war. Camps were frequently very temporary things, and were named on the spur of the moment, and forgotten just as quickly.