reconditioning

Hi folks - is it economically feasible to have gauge reconditioned? Is there a specialist that does this that y'all like to use? Better to buy new or time to hit Craigslist? Please excuse how dirty that panel is, picture was precleaning :-0

I have a 1980 e-35. when I bought the boat the top side looked in good shape and was shiney. Over the last two years a majority of the topside has gotten a powdery supstance on it. I have been told and I do not believe its oxidation. I have tried to buff it out, sand it, used some chemicals...