I think the artist would be pretty upset about the idea of a full-on covering like powder coat or anti-rust spray paint. I'm going to have to look at it to make sure, but generally covering a statue in a 2mm thick layer of anything ruins a lot of the finer details.
But clear powder coat ... that might be the ticket. I wonder if one of the military shops can do that. I'll make some phone calls in the morning. Spray on galvanizing also sounds too good to be true. Let me know what the name of that stuff is, I'm definitely interested.
This board always amazes me ...