Also, I don't think the Q Set actually came with any of the Kenmores (BUT I could be wrong!)....it was an optional accessory. So you don't really need it to complete your original accessories. I remember buying mine in a Sears store in the mid 70s when I was sewing a lot of knits.
On Sears Parts Direct, the needles are still available but now they are just called Blue needles. The feet are no longer made but they are on ebay pretty frequently.
Suzy, if it works for quilting...go for it! But, that wasn't it's original purpose. It just might work there better than it did on knits!