Ignition switch REALLY hard to turn now!

Wouldn't you know at the drags (at tech) the ignition switch won't turn to start! 1968 fish. Really gave me a bad time all day. It had been getting tougher to get to the start position. Should I just buy on from the local auto parts store ( carquest)? Spray graphite lubricant into it? Any input would help! Thx, Kevin