Ah, right. Music might be the single largest issue. Head anis, while not easy to make, could be re-made (and all in all, the project would probably be better off for it), and misc. sounds are available from various free sources, including other FS mods (and even if you can't find any, you could always try to mix and modulate the available ones into unrecognizablity). For WoD, the issue would pretty much only be with music. Free music is definitely available, and we do have a few composers on the forum, so this hurdle might be possible to overcome.
And now that I think of it, who owns the Wing Commander trademark? It just occurred to me that since Origin Systems no longer exist, there might be a chance for WCS as well. Does Roberts have the rights, or did they go to someone else?