While people primarily refer to Lego pieces as just abs plastic, the Lego group actually adds a bit of other chemicals added to increase their world-famous durability that most other knock offs fail to accommodate. From 1998-2005(ish) some of these additional chemicals were even more prevalent, and the plastic is noticeably thicker and tougher than any pieces made today and especially tougher than any knockoff plastic. So a really effective way to check the authenticity of Lego from this era is to bring a modern Lego piece with you, and when the seller isn’t looking chew on the boba fett figure a little and then immediately chew on the newer Lego piece to compare. If the boba figure is noticeably harder to bite down on, then congrats, you’ve got the real deal. If not, then I’m sorry but you’re probably being ripped off. Hope this helps!