A theme we keep seeing time and again is the recycling of lightsaber props. Somehow the ESB Hero was taken a part and ended up attached to other graflexes to form the Skywalker Ranch Saber. Somehow one of the fencing stunts for Luke ended up as a last-minute lightsaber for Vader. Somehow the Circuit board in the V3 castings used in ROTJ closely match the cards made for the ESB Graflexes.
I wouldn't be surprised, since the camera equipment was bought and not rented, if the ANH Hero(s) was(were) cannibalized for ESB. The circuit board was said to be a quick fix given the bubbles disappeared, and we were right about the grips falling off and being screwed on, leaving one off ended up with 6. What if the saber that the grips fell off of was one of the same the ANH props from the first film?
I wouldn't be surprised if RC bought up a few more after he found they were useful for filming, and either used them as back-ups or kept them. The greeblies distinctly do not seem vintage to me regardless.