Like in the Leone movies and some others, I enjoy the two audio versions.
The translation is a bit loose in the first film, but gets more faithfull in the next two.
And here it's a classic: "Met la gomme Chico !"*
It's even sampled by the french rap scene**...
So while it definitely shouldn't be a high priority preservation task,
I'm sure quite a few French speaking people would dig to have a french OT.
(And their kids as well...)
* : Chiquetaba/Chico = Chewbacca/Chewie (in the first film only).
** : like the great Wu Tang Clan did with some excellent Shaw Bros. movies