You might own my old car. My Miata was white of about the same vintage.
All the plastic bits on another one of my cars faded and the finish crumbled back during the 80s. So I sanded all the parts down, bought paint at an auto store and repainted them. Came out great and lasted longer than the original factory finish did! 8 years after I did it, it was still looking good when I sold the car…