Home-brew instructions are here:
and the reason that drove him to that, besides cost:
"It seems the trick to finding the exact one-voltage supply for an eDGe
is that the connector is VERY small for 12 volts at 1 amp."
That said, if you knew what to call the tip (3 millimeters, micro-doohickey, whatever) and
the polarity (is the tip positive or negative?) you could probably find something exactly suitable, new or used, online.