Hi Dave!
Nice shot with some interesting subject matter.
A couple of thoughts? I’ll confine those to primarily the version in post #8 but the first two appear very flat. The conversion looks good to me and I won’t comment on that because you have some comments regarding that already and I don’t know if the scene (book/camera) have any color in them to begin with.
The shot in post #8 also looks a bit flat though better. If this were my shot I would be thinking about what I would consider important in the shot. For me, besides the book and camera in general, that would be the title on the spine of the book. The lettering on the front of the camera is very legible so I would want that brought out. The silver parts of the camera I would want to stand out as well.
As always I would want my background to either stay out of the way or compliment the shot. And the surface would, without negotiation, have to be clean. While its not always possible at the shoot it could be cleaned up in post. The dust specks would have to go!
The background here has some unintentional looking tonal variations, which I would either eliminate or do something else to make it look intentional. In the black BG I would just go for solid black in this case. I’m not referring to the diagonal line of demarcation.
The reflection is cool. Again looking at it the first thing I see is the dust. I would add some local contrast to the book, camera and reflection and probably further dodge the camera’s lettering/silver pieces and the book title to make those pop. Burn down the areas right around the book label and probably lightly burn in the mids in book spine as well leaving the highlights alone and see if I liked the result. I would do a slight repair around the lettering of the book to make sure they come out, but not so much as to make it loose the aged look. Especially the “C” in the first word.
To finish I think I might experiment with some vignetting which didn’t include the camera, book, or reflection along with your rotation of the image. All of this is fairly subtle.