Those ignition switches can be disassembled , cleaned and re-lubed ! Take the c-clip off the back of the switch and it will come apart . Be carefull taking it apart cause there's springs and contacts inside . If anything inside the switch is burnt then replace the switch cause you can't buy the individual pieces .
If you buy a new switch then you'll also have new different keys . That's why I repair the switches whenever possible .
Disclaimer : Don't believe anything I say unless you are absolutely sure that I know what I'm talking about .