I have one and I dont recal anything special about the power lead. As others have noted, the one that powers your PC should do, an IEC connector of the number I don't recall.
Burlington Camera here in Ontario has one without the camera elevation/bellows that they have had sitting there for a few years for aomething like $0-$65. .
Theres things came from the UK. Why search the world?
I am not trying to run them down, but they are not too fancy.
The contrast control unit was slick, but again, just a low power flash with full dump; no thyristor control. Still wish I had not sold that particular unit when I did.
I would suspect you want spares for fear the flash tube will die. The capacitor that runs the tube discharge will likely dry out and go pop before the flash tube.
Powering it up and not firing it for about 20 minutes will help to recondition the electrolytic capacitor if it has been a while since last used, and help prevent it going bang the wrong way.
The modelling light will likely burn out first. The replacemnt will likely be a bit brighter or darker, and the trimmer for the meter will have to be reset after shooting a test roll to link it up and align it with the the flash power, which won't have changed. I associate the from factor of the modelling light with a mid 70's General Motors cars interior lamp, but have not tried to source a spare yet to see if I am right.
Hope these comments help.