I doubt that they were made in 59-63 because K-Mart didn't open their first store until March 1962. It would have taken a while to get store branded blades after that. Besides, the plastic in the injector looks more like the Pella/EMS blades manufactured by ASR. ASR probably holds the patents and makes the blades.
At any rate, the price makes it worthwhile to try a package to see if it is worth buying more.
Also, if it says STEM, its Schick, if it says KEY, its ASR. I have some late 80's Kmart branded injector blades that were made by Schick and not ASR. I was shocked myself.