Taking your ROTJ bucket aside for a moment, Joe.
If that's the kind of price, you can just about confidently bet that no-one will take their prized piece of movie legend apart to recast it.
If anything is likely it would probably be a laser scanned helmet like the Dan Laws bucket.
Under LFL Licence, Museum Replicas are supposed to be working from original ANH props, but as yet we have no idea if they're scanning, re-sculpting by eye, or recasting an original. I doubt very much that LFL will let them recast, so it'll either be scanned, or sculpted by eye.
Please note: I use the term recast for it's original meaning, not as an emotive:
re·cast [v. ree-kast, -kahst; n. ree-kast, -kahst] Show IPA verb,-cast, -cast·ing, noun
–verb (used with object)
1. to cast again or anew.
2. to form, fashion, or arrange again.
3. to remodel or reconstruct (a literary work, document, sentence, etc.).
4. to supply (a theater or opera work) with a new cast.
–noun
5. a recasting.
6. a new form produced by recasting.