The '97 SE was made for theatrical release, not from a digital intermediate, but from the original cut negatives which were pulled apart to create it. The negative segments used to create the new CGI scenes were no doubt saved and stored, but the negative as it once was, with it's original matting, wipes and dissolves, is as good as gone forever (just accept it).
Now the '04 SSE is a different story: as it is made from a DI, no changes were made to the '97 negatives, so in theory you could pull apart the '97 negative again, track down the removed segments in the Lucasfilm archive and reassemble it (not gonna happen).
So, with no realistic hope of the negative, what's the next best thing? Well, it's an interpositive (the stage between a cut negative and the internegative used to create release prints). There's a pretty good chance these exist in excellent condition at LFL for the OT ESB and ROTJ. If they do, they could be scanned in HD for any subsequent digital clean-up and colour restoration.
Why only ESB and ROTJ? Well, LFL or Fox probably have a good IP of SW as well, but there's an even better source, equally close to the negative (one step) for SW, which is the dye-sub prints Lucas is known to have. These are in some ways better than the negative, as they are not subject to the same colour fading over time as the negative stock used on SW. Which means they could also be used as a reference for the digital timing of ESB & ROTJ DIs.
So although I don't think Lucasfilm has the OT restored and on the shelf, I do think they have the capability to put it together relatively easily and for a reasonable cost.