Hey bud, I think it'd be really simple. I'd go with a Mechanicus Grey spray primer for your base, then throw Balthasar Gold on for the bronze metal bits... with a heavy Nuln Oil Wash over the whole thing. You could even due a slight bit of green washes or glazes (emphasis on SLIGHT) to give that patina look.
In fact if you are intersted in going for patina look on your ships, I'd go Balthasar Gold on them, Heavy Nuln Oil wash and then a little green wash glaze.