This is not entirely correct. The sideshow helmet was used for the Axe Woves helmet and other background things, but the Boba Hero helmets, Post Sarlacc and Re-Armored, were changed significantly enough digitally to be considered a different helmet. I have held the real things.
Sideshow will be releasing their post Sarlacc bust sooner or later and I’m sure folks are ready and waiting to recast the helmet, so I’ll spill one detail. The way the rangefinder ear is set up is completely different from the sideshow helmet. That’s the easiest “tell.” But you’ll see overall the shape and proportions are a little different too.
So to be perfectly clear..
Axe Woves (MS2 version) is Sideshow/Legacy ROTJ.
Boba Fett Hero casts (MS2, Post Sarlacc, Re-armored) new version by Legacy.