For your consideration, here is a Kelowna Regatta Hydroplane Racing Pinback Button, Pin, BC, British Columbia, Canada.  It has some wear on it.  There is a little tarnish on the back of it.  The button has a diameter of 2 1/8 inches.  Item pictured is the actual item up for sale and comes from a non-smoking household.  (450.824t-.4px2)