The description of that higher quality upload says they sourced it from a retail demo disk, that's probably the best quality version in the wild. Maybe there's a direct rip of that disk on archive.org somewhere? Otherwise someone could ask them to upload their copy if they still have it.
Blu-ray was just getting started in 2005, and Bravia TVs were 1366x768[1], so the demo disk is likely a DVD. I think someone would have to persuade Sony to remaster their original film, or release it to an archivist.
> that's probably the best quality version in the wild
Probably not, would be my guess. Uploading the very same source video to somewhere else than YouTube (and ideally a place that doesn't do heavy compression at all) would lead to an higher quality version easily, someone somewhere must have done just that.
That's what I meant, that the source video for that YouTube upload is probably the best version out there, as you say the second-hand re-encoded version served by YouTube is inferior. I didn't word that clearly, sorry.
