Ed Hicks,
I just reviewed your pictures again. The marks on the thumb safety could very well be 'GESICHERT' and not a ground off 'GESICHERT' which would make your navy a 1st issue UNALTERED. Which is proper for a commercial navy. That makes me wrong on that point. Sorry.
Darn it, the serial number on your stock doesn't match any of the serial numbers on any of my navies.
Big Norm