They are supposed to be gold in the area around the "E". I had both a 71 142E and 72 145E, many years ago, and I am quite certain about this. Testors model paint, oil based type, in the color gold is a reasonable approximation of the original color. It might also be possible to spray paint the emblems if you can figure out how to mask them easily. If the emblem is an "S" the background should be red. I have seen a number of "E" emblems painted red (and other colors) on restored cars, whether in error, or because the owner preferred it that way, I couldn't tell you.