Thank you Frank for your input and suggestion on the FOIA.
The current owner is an older gentleman who is slowly getting rid of his collection. I've picked up a couple nice non NFA WWII pieces from him as he decides to let them go. This Sten is one he is fond of and is considering selling. I am partial to correct, unique pieces myself. This is one of them, and very cool to me. I'm not trying to steal it from him, just want to come up with a price that is fair to both of us.