I recently read the thread regarding the image of this mask found on the web.
I was going through my pics and came across an image of the funeral pyre helmet.
When looking at it, I couldn't help but make an observation.
When I had looked at the mystery mask pic above earlier, I had come to the conclusion that it was interesting because of the grille that was in it. It was reminiscent of the actual grills used on production helmets, only smaller. When I looked at this image of the funeral pyre helmet, I suddenly realized that the grille is pretty much identical. And while I do not believe for a minute that this mystery mask and the funeral pyre mask are one and the same, in fact, I'm pretty sure they're not, the fact that the grills and their placement are nearly identical suggests a definite connection.
Since we know that the funeral pyre helmet was obviously owned by Lucasfilm and was used in Return of the Jedi, despite its ANH lineage, it is likely that they share the same origin.
I would suspect they were both tour helmets. The good news is, this rules out the original ANH screen used helmet being used as the funeral pyre helmet, as their grills do not match.