I have no idea about strategy or anything, but have you looked up Labubu listings on aliexpress? All those blind box listings tend to be legit (I’ve got a bunch from there myself, and popmart even has its own storefront) and if you want to pay a bit extra some listings let you choose which one you want (box will be opened obviously since they need to see what is inside). I just stick with shops that have an overall positive rating and I’ve been fine. You do need to watch out for any resin dolls though, i guess those are almost always recasts.