I'll have to check to be absolutely sure, but I *think* the music box does make an appearance in the pilot when Barnabas and Vicki share a dinner at the Old House.
I was correct. And an interesting thing is that I did a bit more research and was reminded that the scene in question is one of many in the pilot that had more material shot for it than appears in the pilot. Unfortunately though, none of the edited stuff was restored for the VHS release. But then chances are that's because, unlike the stuff that was restored for the VHS, DC never intended the edited bits (and they are simply bits) to be a part of the final version of the pilot. And as far as our discussion here goes, none of the missing bits have anything to do with the music box's history, so they're not worth getting into.
Actually, it will be interesting to see what he says about the music box and whether or not the comics contradict anything about it...
In the pilot's scene very little info is actually given about the music box's background. It's simply stated that the original Barnabas bought the music box for Josette on the day it was announced they were to wed. And while that might make someone presume that the music box already existed independently of Barnabas and he simply bought it after discovering it, it doesn't totally preclude him from having been involved in its creation. So, unlike a lot of the other stuff added in the comics, it doesn't necessarily fly in the face of what was established on the series in the first four hours. And a very good reason for that is that in 1790, when Barnabas gifts Josette with the music box in Hour 9 of the series, not only is she surprised that the tune it plays is the same tune that was playing when Barnabas first asked her to dance, he explains that he did indeed have the music box specially made in Boston, so for a change the comic merely fleshes out something that was actually established on the series. If only more of the new stuff in the comics fit into the series as well. Though as we'll see later in Book 1, the comic also puts a spin on the music box that was never indicated anywhere in the series...