Actually, based on downloading the photo and blowing it up on my screen, I think the tooth on the ratchet wheel is there, but it is either very dirty or has a bit of corrosion on it...
What concerns me more is the fact that I doubt most of the movement is from Rolex. At this time Rolex used movements from suppliers, and considering the finish on the wheel train bridge (which is marked Rolex) is completely different than the bridges on the remainder of the watch, I'm guessing only that bridge is from a movement touched by Rolex. The other bridges are not just missing plating, but have a straight grain finish applied, where the wheel train bridge appears to be more polished, with no visible graining on it.
Based on this alone, I would pass.
Cheers, Al