I can't tell for sure but I would say it's similar to an eye lash type yarn. You can always contact the company and find out. Or have a look a the ball, there should be a gauge chart on the lable that you can match to another type of yarn.
Patons Ritz yarn was a bulky yarn. It was about 12 ply.http://www.ravelry.com/yarns/library/patons-ritz
because its pertty
Ply Gem Industries Inc. is a subsidiary of Nortek Inc
This does not seem to be a current yarn. I suggest you contact Paton's via their website.
Weight: Bulky / 12 ply (7 wpi) Gauge: 16.0 to 18.0 sts = 4 inches US 9 - 5.5mm
Patons has many weights of Tweed wool, so look through the Paton link and see if you can find the specific wool you are looking for and have an answer that way.
Ply Gem Industries Inc. had 4,079 employees in 1998
It appears by looking at the Patons link I attached, that this yarn is still available. If you don't know where to find it in your area, contact Patons and they would be able to direct you to an online or retail store in your area. (at the top of the page of the Patons link, is a Store Locator tab that you could also click on).
Ply Gem Industries Inc. had estimated sales of $790 million in 1998
Patons
I searched and was unable to find Patons Camelot Wool. The best I can figure out is that you might be referring to Patons Kroy Socks FX in Camelot color. So, going by that thought, it would be a sock-weight yarn; or category 1 fingering weight yarn. Therefore having a ply of 4. If I've totally misunderstood what yarn you're asking about, I've attached some URLs which might help you to translate the information you have on the yarnband into ply.
Alternative yarn choices: Patons Symphony or Wool Tweed DK