I've long forgotten the source, but circa 1980 Boba's outfit was referred to as "old shocktrooper armor" and I probably wasn't the only fan who decided that this was something worn during the Clone Wars.
Isn't there an early costume test photo where Boba's armor is pristine and white?
One of the early fake trailers for Episode II had a shot of a whole squad of guys in Fett armor. The maker must have remembered the same stuff I read.