Something is very goofy here. First, the V serial numbers did not go that high. By the time they got to 990xxx, they were all S prefix guns and these were shipping in the Spring of 1948.
Moreover, the swivel on your gun is not correct for a Victory Model (you did note this difference in your post).
Given the other markings on the gun, this could be a so-called "pre-Victory" and that would put it in an entirely different numbering sequence. But it would not have a V prefix under those circumstances. I see something under the swivel on your first photo, but I cannot tell what it is. Perhaps you can post another picture with the swivel flopped over the other way so we can see what is there. While you are at it, please post a photo showing the whole of the gun's right side.
Also, what is that on the frame, below the thumb piece? That picture is far off and blurry, but something seems to be stamped there.