Jason Cloessner, Lipsey’s Senior Vice President & Product Development Manager, has stated in Primary & Secondary podcasts that they're exclusive to his company for now, but not a limited run. He further said that they put in an order for a second batch after the enthusiastic SHOT Show reception, and they'll keep ordering them from S&W so long as there's demand for them.
My suspicion is that these will tie up a significant percentage, if not a majority, of S&W's aluminum J-frame production capacity for the rest of the year.