Anytime the "Aregent Silver" issue comes up I have a laugh. I suppose Ford was trying to be up-scale using Argent in describing silver as Argent is French for silver! However, getting the correct silver is important...
Not trying to be disrespectful here at all, but I saw the posters' question as an opportunity to point out that not all silver enamels are equal, in fact that Ford Argent is superior to the many different brands I have tried.
Additionally, don't even try to clear coat over the various brands of silver enamel, you will immediately be disappointed in how it looks.
Try wiping off an air cleaner that had been painted with other brands of silver enamel using solvent. Guess what, the paint wipes right off, but not so with Argent
Ford Argent dries glossy, as if there is some special acrylic the other brands don't use. Pick any name brand silver enamel that is labelled as "gloss silver". It really does not dry glossy, but I think they try to fool you because it is shiny when new, but that shine wears off real quick, and many of the silver enamels are pourous to the point that they really don't protect the metal well against rust. But Argent DOES.
Here's a test. Take a chain link fence post and paint it with a name brand silver enamel then take another post and paint it with Ford Argent and leave them both out in the weather. In no time at all you will be convinced that the name brand silver doesn't cut the mustard.