I would still prefer the Caddillac paint if it were me. Easier to get, no as much clear to have to use, etc. Go to a caddy dealer or online and look for that paint color, it looks really good and I bet you 95% it's what your looking for. If I am wrong you can punch me.

But yeah it is called plum or plum purple. One of those, but the dealership will know what your talking about, just tell them it's an old color from the 60's or 70's.