They didn’t dust off an old Artoo for TFA, and even built a new improved Threepio suit for Anthony Daniels, so I can’t imagine using anything left over from Episode III now. Heck, they could have easily used the actual burned Vader mask from ROTJ, and they didn’t.
Of course I don’t mean the actual worn suit from 12 years ago but the “ROTS version” that was used with its stupid weird helmet and non-accurate armor or anything that makes you think about that. And I almost don’t even want to go there but there better be a different guy inside. But I’m pretty confident that they avoid these mines.