No need to replace the steering lock, simply buy an emulator "£25-30 on ebay, unplug the steering lock plug the lead into the emulator and bingo, problem solved..
Unhook the negative terminal with the ignition lights on, this should reset the ecu and then enable you to start the engine, next, turn it off and on again andlisten for the buzz from the steering lock ... chances are that you won't hear it, so...