Dream on. Actually, there were two English dubs. The one that was abridged on the Super 8 home version was made by the same people who did the French dub (En cinquième vitesse), with some of the same voices. The version shown in the US was entirely redone, with different actors and a different script. A 35mm IB-Tech copy is on file at the Academy of Motion Picture Arts and Sciences' Mary Pickford Center for Motion Picture Study. Surprisingly, that print contains two brief moments of full-frontal that are deleted from every other copy I've seen, and that explains the X rating. When I say brief, I mean brief - only a few frames each. Unsurprisingly, the US version is missing other scenes and shots contained in every other version I've seen.
In all likelihood, the earlier English dub probably survives at some vault rented by the heirs of one of the original producers (Panda Cinematografica S.P.A. and Les Films Corona). Can we ever find those materials? Have the labels fallen off of the cans? Have the film and tape turned to goo? Will the owners and their lawyers allow anyone within a mile of the vault? Good luck. As for the US version, it would cost probably tens of thousands to get it digitized. Last I heard, Tinto owns the rights to the movie now (though probably not the underlying rights to the novel), and Cult Epics I think still has the US license. They would probably agree to a transfer if we could raise the money. There's more info here:
By the way, the 35mm print contains much more picture on left, top, right, and bottom. Because the lab printed every other shot out of frame, though, the video copies are all cropped to prevent the tell-tale black bars from dancing all over the screen. That problem would be easy to correct with a 5K digital transfer.