Yeah, you're right. I read your question wrong. The Broadcast Code for 68 Power Disk brakes is "CH".
Yours looks similar, but notice how close together my letters are compared to yours. Also note that the top of my T isn't as wide as yours and the outer "legs" of my W go higher than the middle part. Yours is equal all around. I'm no good at spotting restamps, so I'll let Kurt chime in!