A dilemma indeed, but for most I believe easy access to the digital copy (mkv, mp4, etc.) would be good enough for most people, but the people who want a proper custom box set is the tricky part.
Well, if Disney officially published the blu-ray of the original trilogy, with a beautiful packaging, the problem would be solved!
IMHO, if we let these ebayers (like this “LDSEntertainment”) sell the original trilogy at such a price, it will put a little more pressure on Disney and Lucasfilm to release it officially.The only thing we can do is advise Disney/Lucasfim, and let them solve this issue (which is as much their issue as ours).
A petition perhaps? I’m pretty sure there are many petitions about the same thing so I don’t see how Harmy can get the attention of Disney.