You may be correct about the unit and these men in it, but their age and the cut of those suits they wear leads me to believe this is a postwar outfit to protect the community or that these older veterans arranged to have identical suits in order to pose for this photograph. The arms they shoulder certainly look like Civil War pieces and they deserve credit for keeping them and themselves in such good shape several years after the war in order to all have them for this shot. Just guessing, I would say this photo was taken about the 1890s. It's a dandy, though!

Bruce Nichols