Possably a grandfathered one? Not sure but I see used USP's tagged in MA for hundreds more than I see new ones for here. Was told it's because they were in state prior to them being banned.

Yeah, I thought about that, however I think the ban was like '98 and I believe this gun was manufactured in Germany in like '05 or '06. At this point I'm thinking that either the list I found isn't entirely up to date (it lists the p2000sk but only in .357 or 9mm but not .40) or, as some have suggested, this store just sells what they want thenl claims that it's the buyer's responsibility to know the law.
Thanks for the reply