Buying a roll of the Ultra Endura and cutting it as needed should be very easy to do in the dark with a simple guide setup. It's also pretty inexpensive bought that way.
Kodak Royal Generations is one of those papers that is supposed to be suitable for both digital and optical printing. I don't see any warnings from Kodak about cyan shadows. http://www.kodak.com/global/en/consumer/products/techInfo/e7009/e7009.shtml Do you have a link to the Kodak warnings about color balance when using this paper for optical imaging? It would be really cheap to buy a roll of this paper in whatever width one deemed convenient to handle and store.
You're right, it doesn't mention a problem there. Perhaps it isn't a pro paper and Ultra Endura is the last pro paper meant for optical use. Sorry for spreading misinformation.