I’m excluding SE dubs from this discussion because I know nothing about them.

The Japanese GOUT discs have two dubs apiece for SW and ESB, and one for ROTJ. All of these are preserved, I believe, on a.b.starwars. That would be the theatrical and home video (VHS/Laserdisc) dubs for SW and ESB, and the home video dub for ROTJ, in two-channel Dolby Digital form. The home video versions of these are available in the Despecialized Editions. I typically don’t keep more than one dub around per language, so I no longer have the theatrical dubs.

I don’t know how many iterations of the home video dub there are–I don’t think the actual dub was ever done more than once, but there were other audio revisions for SW in 85 & 93, and ESB and ROTJ in 93, at least in the English releases. That means if you include the same dub overlaid on different soundtrack as a different dub, you get potentially four SW dubs, three ESB dubs, and two ROTJ dubs, not including SE dubs.

FWIW, the English 93 audio revisions for ESB and ROTJ had no significant content changes other than a missing sound effect in ESB, so it may not be worth collecting this particular variant.

I don’t know anything about a TV dub that’s different in any way from the home video dub. I guess it’s possible there are variations where the broadcaster dubbed over the crawl, etc.