The highest quality source in the universe is in George's basement - a Technicolor IB print. And even that is at least three generations from the original negative (Negative>Inter-Positive>Inter-Negative>Print), which has long since degenerated into nothing. So in the purest sense, Star Wars is already gone forever. But if one had access to George's - or one of the few remaining other Technicolor IB prints - and was truly, extraordinarily clever and patient, today's tools make it as possible to get back to the look of the negative as has even been possible before.
That is the task to undertake, in case the future sees a reversal of position on the matter.
_Mike