No evidence that the regiment had a battleflag.
Parts of the 3rd and 4th Alabama Senior Reserves were involved in the last battle of the Civil War. This took place on Alabama soil, Easter Sunday, Apr 16, 1865. If memory serves, elements of Clanton's Brigade and the 7th Alabama Cavalry with the Alabama Reserves formed the line nw of Girard as shown on this map.
http://en.wikipedia.org/wiki/File:Sketch_of_the_Defenses_of_Columbus,_GA.jpg