According to both of Paul Newitt's books, the stripes came in 4 colors: white, black, red, and blue. And of those 4, only the blue stripes were "metallic", or reflective. (The stripe color tended to match, or at least coordinate with, the interior color. I don't know that I've ever seen the red or blue stripes in person, although I've seen photos of both.) It doesn't matter when your car was built. Also, this is one thing that a Marti report does not identify; the codes on the car tell you exterior and interior colors, but not stripe color.
By the way, at least one Mustang parts vendor sells the stripes in gold. Just keep in mind that it's not one of the original factory choices.