For fun see if you can post some better pictures of the engraving.
As to who would stamp an improper grade stamp into a Parker, unfortunately throughout history there have been all sorts of people who dared to do all sorts of really unfortunate things. Including impaling your stock. Sorry about that.
Wasn't Vlad the Impaler from the Carpathian Mountains? As the Parker stock guys largely hailed from the Carpathians, who knows one of his descendants might have worked on your gun.
Looks like you have a great gun to learn on, and when you get done you will have something you can take pride in with pictures of where it started. Anyone can buy a fancy gun in a store. To bring one back takes something extra.
The Fishtails tend to come from that year. Always an interesting option. Be forewarned that Parkers can be addictive.