Wow. No responses or advice. That’s great. Does the NE Plant Society even exist anymore?
In case anyone is reading this thread I thought I would share the place I finally found. Tech Air, 576 Christian Ln, Berlin, CT (860) 229-1834 www.techair.com
They don't do refills only exchanges. They took my old fire extinguisher red tank and swapped it for a silver one. It only cost $16 to swap out a 5# tank. I definitely recommend the place.