Yes, the center picture is the actual item (as stated- broken). The left picture and the right picture are photographs that I found on the internet that show the details of what the original looked like. The left is the obverse and the right is the reverse ("flip side").
I believe it is rare because these were made special in England and brought to America in the early 1700's to be given to the high-ranking natives in an attempt to get them to side with the English troops that were here. I'm just 'guessing' that very few came over and that fewer survived the past 300 years.