Several manufacturers will have information of this type. Try Mitchell Fibercon (Pittsburgh, PA), Dramix Fibers (Seattle??), and Forte Fibers in Atlanta. Covers metal and polypropylene, collated and non-collated fibers. For general info on fibers, check ACI Committe 544 reports for overall source.
The largest supplier of both polypropylene fibers and steel fibers is Synthetic Industries, in Chattanooga, TN. Call Mike Thompson - 423 892 7243. Many rehab jobs have been performed using both fibers in both shot-crete and cast-in-place applications.