FIG. 1 is a right side view of a sighting device showing my new design; FIG. 2 is a top view of the sighting device shown in FIG. 1; FIG. 3 is a rear view of the sighting device shown in FIG. 1; FIG. 4 is a front view of the sighting device shown in FIG. 1; FIG. 5 is a perspective top, front, and left side view of the sighting device shown in FIG. 1; and, FIG. 6 is a perspective top, rear, and right side view of the sighting device shown in FIG. 1.