I don't know about the shelf life. I bought two spray cans, used about one doing the wheel, had some left but tossed it. I think I still have the other can in storage.
As for anodizing the frame it can be done, the frame would have to be free from all contaminates, like paint powder coating stuff like that. a Hard anodize would last longer and resist scratching much better than a color anodize. That anodize will fade in the sun also.