I am not sure if these are actually anodized or painted, (my v6 is anodized) if the scratch is down to the metal then i think you will have to live with it or seek a professional to correct that.
If it is paint then you may be better to visit a car paint shop, and see if they can supply one of the rub on paint leafs or maybe a touch up pen - that's only if they can match the colour.