I have two from 1981... One Basically NIB and one I used... Pistol pacs that is... I am not sure what that piece is it is not original to the pistol pac though... 
My dan wessons shoot great, I have another as well as the PP's. 
can I ask what ya got that for ? I need to move one of mine one of theses days  Like I said ain't shot one of em in thirty odd years, won't likely soon either- don't see my other breaking....