Hey! Well, I don't know the dimentions of a nb diaper, unfortunately. But here is a link for some free diaper patterns. Some are one size, and some have multiple sizes...there might be a small or newborn in there somewhere.
I've been to all of these, as well as the others listed. I also made my own pattern, the dementions before sewing are:
back from tab to tab: 15"
between legs: 5"
I put elastic on the back to help prevent blowouts (baby hasn't been born so I don't know how well these hold up) and I used aplix closures and added a snap in front to snap down for cord healing. My soaker is about 3"x9"
Being new to the lingo, what exactly is the rise? The diaper I make is about 15" from back to front before sewing. After sewing and folding it, it is 6 inches from between the legs to the top of the front.