As of this writing I have the physical adapter to connect to the unit, but not a power adapter with enough amperes to actually power the thing. The original PSU supplied 9 Volts of AC power with roughly 2-3 Amps of available power. The supply I have is delivering 9 volts of DC power which I've read it'll take just fine, presuming it has enough amperes to power everything- the actual power supply on the VIC-20 (the parts under the black metal heat sinks) are doing all the heavy lifting that later power supply bricks would be doing.
Commodore only made this variant for a little while before discontinuing it in favor of the much improved and better known VIC-20 "short boards" which are about two-thirds the size and half the weight. Rather than tear our show-ready one out of storage to show you, here's a picture I borrowed from the 8-Bit Guy.
This one is a sharp 2-tone yellow after all of these years. The unusual contrast which makes me think it's two different halves that were snapped together at some point, with the top half being considerably newer than the lower half.