Where can I get a new ignition switch for a Ford Fiesta Mk2 (1986 model)?

Some kids tried to hotwire my car by breaking open the ignition switch and trying to start it this way (this works- as this is now how I have to start the car) The ignition barrel is intact but the switch on the other side is broken where they cracked it open which means the turning of the key does nothing. I would like to replace the ignition switch so that I no longer have to hotwire my own car to start it but have no idea where to get one from. Would appreciate any ideas?