That Kenmore is sure in great shape, I don't recall that particular color. Im just drooling over it.
It is a Ryobi product Guy, Probably from around 1990.
As far as the Singer That would be the correct bag for a BOL machine, but the cord looks like a replacement being that it looks to long for that vacuum. I could tell better by seeing the plug. The approximate year of the Powermaster is about 1980-82. Could you post a pic of the bottom if you get a chance?
Both vacs are very nice and cleaned up very well. If you think of parting with that Kenmore think of me ;~)