I think that the number is a paint manufacturer number, for the following reason; I have the correspondance between the first buyer and the factory for my car, and there is no reference to a number. When it comes to the paint the factory always use the name of the paint in the correspondance. This is no proof of what I say, only an idea. As to your paint I propose "Spies Hecker" paint number 6338 006/ 93467, blu met. This is a wild shot but perhaps worth asking your painter to mix a sample.
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