The power supply is definitely not in the picture and it is useless without it. I have two scanners, one with a power supply and one without. I've not been able to track down a replacement power supply.
I will look into the availability of the power supply, as it would be good to have a spare. These scanners are awesome.
I ordered one from HP direct in Australia and was about $25 .The part number was L1970-80003 Universal adapter 12v/1.25a
Hope this helps someone