killrust enamel is ok, $12.50 a can when Supercheap has it on sale.
make sure it is at least a week old before you spill petrol on it, otherwise it will fry up and peel off.
also the gloss fades quickly, unless it is polished and waxed once a month
VHT make some decent paint too, their Barrel Case paints are chemical resistant too,
around $15 a can