I have loved 58 impalas since I first saw American Graffiti. Bought my first one in 1975 for $625. I drove it from New Mexico to Iowa to go to college 5 days after I bought it. Drove it back and forth on Summer breaks. Finally retired it 5 years later. I drug it every where I lived for 42 years...
Try getting a paint chip chart from E-bay. There are all sorts of years and auto brands, With the right chip, it should be easier for someone to replicate.