I haven't been to check this lately so your mileage may vary. But be sure to check your local hardware stores supply of cheap cordless drills, you might have luck and get a power supply.
This problem was infuriating me as I was even told at one point its legally impossible to get linear power supplies into NZ anymore.
Fortunately I happened to spy a friends el cheapo Dick Smith Cordless drill had a nice NZ made HFA, 1Amp Linear Power Supply, (tip +ve which I'll eventually change) swapped him for a spare switchmode and presto happy sammichSID.
And cheers Wilba again for the amazing kit. Need to post about two minor cosmetic problems I've caused and getting midibox Sid Editor working in Tiger but otherwise I've been really digging playing the sammichSID over the last month!
Also another random tip people probably already know. Insert leads make a great stereo out cable for people who hate adapters!