The anodizing I'm thinking of trying is Type III/Industrial Hard coat, 1 to 3 mm thick. No coloring avaliable except for black and olive green due to the increased thickness of the anodized layer. The anodizing process for industrial hard coat is on and in the aluminium, where Type II/Type I anodize is just surface and thin.

No marine enviroment to worry about for me, I'm in a semi arid climate.