S&W gets it's mags from MecGar, as do several other pistol manufacturers. Since the "Gear Up" caused by the Socialist in Washington, all the firearm manufacturers have had a 4 fold increase in product demand and MecGar literally cannot catch up. I do not know if MecGar has a U.S. plant, or if everything they make comes from Italy. I think the later is correct. I do know that mecgar will not answer their phone(at least as of several weeks ago), and the statement on their web page is almost hateful about contacting them for information or product.
Methinks that the Firearm manufacturers should reconsider who and where they get their magazines made, huh!