For your consideration, here is a 1992 Shop Rite 40th Anniversary 1952 to 1992 Pinback Button, Store.  It has a little wear on it and some tarnish on the back.  The button has a diameter of 2 7/8 inches.  Item pictured is the actual item up for sale and comes from a non-smoking household.  (347.320y-.4px2)