Seeing that the “Extended Death Star” battle is now no longer being a thing, could it be a possible deleted scene under your Bluray Special Features?
There’s a hell of a lot of work that would be involved in recreating that whole scene in HD and i feel it would be time best spent on working on finishing the trilogy, so it’s a no i’m afraid.
You could just include the 720p version that is already completed; no need for deleted scenes to be full HD