What is the absolutely correct blue engine paint color for a 74 Duster?

I remember the 1975 Sportsman Royal Van my dad bought new when I was twelve pretty clearly. Its 318 had a definite turquoise look about it, to the point that i commented on to my dad. And as for my engine, the valve covers were pulled off and replaced with Mickey Thompson's when the engine was only seven years old. They then spent the next 38 years sitting on a shelf in my parents garage, so they probably aren't as far off as you're thinking.
Can you add a photo of your blue valve covers?