Well, since I don't have any of these cases on hand I've had to do some creative calculations based on what you've posted thus far soundwave, plus using Shenske's 8-disc poly case template, and Shenske's Universal DS case.
Standard CD Jewel Case and a DS case are pretty damn close to each other (possibly a MM or 2 difference) in height. Standard CD Jewel Case is about 5mm longer than a DS case.
So, based on those and everything else I believe the size for this template should be 3320 x 1370. I've printed one and it looks right, but again with no template to go own I'm using an assortment of standard jewel Case, slimline jewel case, and DS cases to go of.