Steve Rutledge is also a student of the Navy guns, I asked him if it might be a match gun or trophy rifle:
"It doesn't look like one to me. Has hooded sights which would only be on A grade unless they added them. Stock doesn't have the typical finish that I'm used to seeing. Unfortunately, we can't see if there is an "A" or "B" stamped on the flat of the pistol grip which I think is always there. Most of the ones I have seen have fairly ugly birch stocks."
Let's see what Jim Adell says.