nuts are cut from nut blanks. in the case of a Fender clone like yours, you're looking at a 1/8" wide nut blank that's 1-3/4" long or longer. since it's a USACG neck, you could have a flat or radiused slot bottom depending on what Dan ordered. you can get nut blanks at any Guitar Center or on-line at places like Luthiers Mercantile Internation or StewMac
personally I would have real concern about a nut that's pre-cut on an instrument other than the specific one it's intended to be used on. it only takes a few thousandths of an inch for a nut to be too high/low for optimized playing, or too wide/narrow for the nut slot. this can only be fit on the exact neck the nut is to be installed on.
my recommendation would be to get a warranty agreement from Dan to cover the cost of taking your bass to a local shop and having a new nut cut. it's cheaper than r/t shipping, and you'll end up with a nut that's right for your bass (vs. something that's close enough to probably work good enough)
all the best,
R