Liquor Outlet in Boonton has a nice selection. Lots of sixtels available and they update their inventory online pretty often: https://www.liquoroutletwinecellars.com/pdf/keglist.jpg
I get mine from Bottle King in Chatham. I go there 1 week before I need the keg an order what I want. Not sure what craft they keep in stock.
they've sent to Brick Farm Tavern once, and to Stirling Tavern (sister to Stirling Hotel), and I think they've been on tap at Cloverleaf and even Poor Henry's once... but no, they have not sold to the public at all as far as I know. hard to do that when they can't make enough to have it last long enough in the tap room