Rather than try and cobble together a North American power supply for the CHESSmate, I ended up getting a 110-120V to 220-240V adapter. Since I had the machine apart and the electronics checked out, no rust or leaking caps, I reassembled the CHESSmate, plugged it in, and it powered right up.

Since there is no screen, you really need to have a physical chess board to keep track of the moves when you play against the machine. I dusted of my old chess set (literally it has been on a shelf for decades) and my equally dusty chess skills (which are pretty anemic to begin with). You can see my game in progress above. Notice I was even able to castle.

So not only am I now able to make precise measurements when modelling the case in Fusion 360, when the time comes I will be able to use the CHESSmate to validate that my emulation is running correctly. Bonus!