I've spent the day with a number of original helmets, including an ANH and RotJ Stormtrooper - and have looked at this again. However IMO (and it really is only an opinion) - but what we're seeing is just the same reconditioned ANH helmets.
We know for a fact that 2 Hero's survived ANH (for the Holiday SPecial) so its possible that one lost its lenses so could be viewed a Stunt/Hero hybrid - i.e. an ABS "stunt" style helmet IF they replaced the lenses (again remember the one currently in the archive has no lenses - not sosafe-keeping from Lucasfilm I'm sad to say).
But when I look at these two - I see ANH helmets, not RotJ
As far as the one on the right- see more ANH bump under its eye than RotJ...
...and IMO this photo was taken 1983 for the Star Wars exibition (I forget whether it was Harrods or Selfridges but I went to both)
The troopers in the Getty photo are not the same as this. The Getty one was 1980, this is 1983 and the troopers are different.
I'm certainly not closing my mind off to the possibility, and I applaud Paul/TM for provoking this healthy debate. However, at the moment I just dont see it. But like I said, its just an opinion
Cheers
Jez