The system (4 cells, junction box, display box) was made by Tara Systems and is a model TR-1-NK. I think I got it from McMaster-Carr
Picture of one of the load cells at http://www.pbase.com/image/132247153
and of the display at http://www.pbase.com/agamid/image/84072359
The top of the junction box (4 wires protruding through bushings) can be seen on the wall behind the flange of the carbonation stone and just to the right of the rightmost vertical black steam hose at http://www.pbase.com/agamid/image/122872673


