If I am correct we are talking the bits where in the Calais would normally be the very fake looking woodgrain?
Someone like Rare Spares might have them as an aftermarket product but I would more than likely try a wrecker first and perhaps ring Holden to get a price so you know what they are brand new.
I've been caught before where Holden was actually cheaper buying it brand new than it was to get it from a wrecker.
Then again a bit of chrome paint would do the trick although how it would go in the heat is another thing. Spray paints in the can generally peel off then again you could enquire at your local crash repairer and see whether they can spray them for you.
