Amazing!

Yes, they do indeed look to be from the same source.

My copy has the UK certificate at the beginning, so I would assume this was cam'ed in England. Funny that the Treadwell is NTSC, then.

I agree it seems to be several generations closer to the source than mine, but with analog video (and standards conversion) it may just be a couple recordings removed.

Could you check and see if the Treadwell's version has Luke felling a speeder bike with his lightsaber, and the A-Wing crash through the Star Destroyer bridge present? I believe they were both missing from my version.