I received the two Colecovision USB Plugs, and tested them both.
I spent several hours with each, and both fit well and worked great (*).
I used the exact same 17 watt 3.4 amp USB-C power supply previously mentioned by HDTV1080P, and the exact same 5A USB-C cable as well so I can confirm that the combination has been awesome so far.
It worked with any peripherals I threw at it, but I do not yet have an Adam to test.
Kudos for a great quality product!
(*) I did have a few graphical glitches at first, but its the same glitches I had with the original power supply because when I wiggle the power port at all it occasionally happens. Most likely fixed with some solder, as that happens frequently with Colecovisions. Am I right to check that first? The power switch had previously been cleaned and seems solid.