You should consider donating to Poita’s 1997 Special Edition 35mm 4K scan project!
Holy biscuits. Googling suggests 35mm film is about as close to the original stuff as you can get(?). I may well donate, but I would probably want to try and continue with my efforts a bit, unless it’s likely to be fruitless (both because ‘I’ve come this far’ and also because my max download speed is 120KB/s (the area I live in is rather remote), besides the fact of which I have no idea what the proper etiquette is regarding discussion of these matters on this forum, regarding understandable piracy concerns, etc). It also looks like it’s just the first film so far in that thread, although it seems they’re also trying to source ESB and ROTJ?