I think I know why nobody is building Chexx machines.
I did an incomplete parts list from Happ
dome, 2 net assy's, corner deflectors 4, puck, ice surface, 2 goalies, 10 players, 10 player gearboxes.
in excess of $2500. I reiterate it's an incomplete list. This doesn't even include the scoreboard, the cpu, coin door, or materials to build the base and control rods, grips....
only 10 players, 10 gearboxes, 2 goalies is over $500. That means making the base the tracks for the control rods, the rods, the computer controls etc yourself. I think you'd have to buy the scoreboard.
Looks like this sort of machine is a resto project type thing only.