Would it not be more cost effective to hard anodize the levers or anodize them in some color? You can anodize in any color imaginable and you can hard anodize the levers and that will make them as impervious to the weather as my stainless brake clamps.
If your clutch lever is anodizing, try riding more, Mine shines like new money. Or are you shifting without a clutch. I admit my brake lever has some funny stuff growing on it