Luke, standard colours listed in Rinsey Mills' "Original Ace and Cobra" book, taken from a factory sales brochure:
Black*, Red, Maroon, Bright Blue, Beige, Grey/blue, Cream. * = offered with black upholstery.
He also lists a representative selection of colours as:
Middle Brunswick Green, White*, Svecia Red, Gunmetal, Dragonfly Blue, Pacific Green, Mist Green, Silver, Oxford Blue, Heather Metaline*, Vermillion, Mail Red*, Steel Blue Metaline, Black Pearl, Rouge Irise.
Hope that helps (to confuse matters!).
Mine was painted a Porsche silver.