If you use Usenet, all three scores are still available (assuming your Usenet provider has decent retention, which most seem to these days). Following this link takes you to binsearch, where you can search Usenet. I've tailored the search so you can see just the Return of the Jedi tracks. You can create a Newzbin file (nzb) from this page, and feed that into your Usenet binaries downloader, and you should be good to go. If you don't use Usenet (and I know a lot of people don't), I've found that Astraweb is a good deal. For ten bucks you can download 25 GB of stuff, stretched out over however long a time period you want. Or if you do a lot of binaries downloading, you can get unlimited downloads for ten bucks a month. GigaNews isn't insanely expensive either, and I believe they at least used to offer a free three-day trial, so that's worth a look.
Anyway, the links to the search that will show you the Return of the Jedi (in FLAC):
These aren't my uploads, but someone told me a while ago to search Usenet for *XS* OT Remastered Scores, and there they were. All three scores are actually there, but since you were only looking for Return of the Jedi, I tweaked the search that I linked to so you'd only see it.
Hope that helps!
Eric
P.S. If you (or anyone) is looking for a program to download Usenet binaries (after getting an account with Astraweb or GigaNews or somewhere), SABnzbd gets a lot of good reviews. I'm on Linux and use LottaNZB (and have used Unison on Mac OSX in the past), but SABnzbd seems to be well thought-of, and also runs on Windows, Mac and Linux. SABnzbd.org should tell you everything you need to know about it.
P.P.S. I forgot to mention, but if you click on the poster's name at the previous link, you'll also find the two LP rips released alongside the trilogy remasters. And, The Empire Strikes Back Audiophile Edition is also on Usenet; just follow this link for another binsearch Usenet search:
That's all. I promise! (Unless I think of something else)