I have personally loaded hundreds of KW-7's with 7314 cards, hundreds of times.
Thing is about the Walker thing, is the Soviets didn't get the cards until a few weeks after they were used and could only decrypt traffic they had previously recorded.
Yes, it was real treason on the part of the Walkers, but it probably saved a lot of misunderstandings that could have been deadly.
There was a Soviet AG that thought it was cute to spoof the SPS-26 tones that we used to communicate with the submarines. This went on for a couple of weeks, and then all of a sudden stopped just after midnight Charlie time. I figured Moscow Center had finally sent the AGI a message that said, “You realize that one of those codes is ‘Sink the Russian’, don’t you?” Now I know they were probably responding the message we got from CTF 69 saying the same thing.