I made a quick stopgap power connector for testing an
Amiga 500 by soldering the leads
of a discarded rack server power supply to 5 small nails, worked just fine.
A small bit of info that may (or may not) interest you:
The strange female connector soldered on pcb of any amiga computer can
be xchanged by a DIN-8 PCB female connector. Just unsolder the square
beast, and solder the common DIN-8.
I have to do this in mostly all power-supply-less amigas I get in Brazil :(
Maybe you're interested in this small piece of info :)