Decoding original color

[Cermolovich]

Hi! Im restoring a '67 chevy truck and im having some troubles finding its original color. I have the code and the name, its PPG's light blue 507 (12846). Now here's where the problems starts. I live in Buenos Aires, Argentina, and when i went to ppg's official distributor, they couldnt find the formula for that code, and the closest one was from a lates 80's blue. So I was wondering if any of you guys know other way to find that formula, or even better, if anyone already knows it. Thanks a lot