How to run 12v radio off AC current

Hey I have a 66 dart, and I have the old AM radio. I want to be able to plug it in, in my tool shed and hook up a speaker to it and listen while I work.
Is there some sort of Wallwart plug I can get that will give me the voltage and mA that i need in order to run the radio??

A power adapter for an old cordless phone, router, modem or something like that, that puts out 12vDC and a minimum 1 amp output should do it as well.
Before I run out and buy something I check and see if I have something that will do it first.:D