When I first contacted CT several years ago, things were more informal. But more recently, yes, they want the 'NDA' before even talking to you. So I signed one, and then their sale reps were willing to discuss with me on the phone and by email what they had available. Besides the lime green, they also had yellow in much smaller quantities smaller than 99 meters, but also shaded and not a solid color.
One might need yet another team of lawyers to figure out exactly the meaning of the 'NDA,' but since I was just buying some material and not retiring from the CIA, I went along with it, just to find out what was available. You might contact William Zila, who posted on a recent thread about using a .5 ounce 30 denier reflective cuben. You might also try contacting Joe at Zpacks, as he uses and sells several varieties of cuben and probably would know what might be available in a reflective material.
You might also contact the people at kitebuilder.com, as they sell a variety of sail cloth to kite builders, and might have something in bright orange. All the sail cloth I have seen, whether nylon or polyester, and whether woven or non-woven, has been a very stiff fabric with little or no elasticity or drape of the kind that light woven fabrics have. However, it comes in weights down to around one ounce per square yard, and might be suitable for your purpose. It is noisier than cuben, however. Note that weight of sail cloth, also provided in ounces, will be more than it actually is per square yard. The weights provided go down to as low as a half ounce, but the material will weigh around an ounce per square yard.
You might also look at Rockywoods or some of the hunters' sites on the web for bright orange material. Unfortunately, it tends to be of a heavier weight than what it sounds like you are looking for. There is currently some blaze orange silnylon on ebay, but it does not state the quantity: http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=390361540605.
You could check out the several reflective space blankets that are sold at camping and pack shops, but while very light they are probably not durable enough for a poncho.