I've got Squall's necklace from Ebay, so I'm pretty sure it's a copy, but I'm satisfied with it anyway.
It has the .925 engraving, but still, I don't think it's the offical product. I also got Rinoa's necklace with her and Squall's ring on it (a copy too, I bet). But, it really sucks about FFX's, 'cause Tidus' necklace is so cool! There's also the earring, but I don't think I'll get that. I really want the Blitzball though. That looks really cool.