On the Vintage Kenmores group page on Yahoo, someone replied that they may have a set to sell. No, it's not a need, but it would be fun to search for. From the Sears web site I found that they are C-cams and are orange and green(?) I think.
Today, I played with the 99 in the case, the 128 in the case and the 66 Red Eye Treadle. I am happy to report that 2 of the three are in working condition. The 128 has something that is making it run a little rough. Seems like something is not moving very smoothly, but the motor runs well, I've got the tension adjusted. I had to use my older treadle to wind the bobbin because I'm missing a wheel on the bobbin winder. I borrowed the clutch washer from the Kranky Kenny I have in the garage. It's not running anyway, so I didn't think he would miss it. So, it SHOULD be working. A little more oil everywhere and we'll try again in a few days.