That cover looks very nice.
As far as finish is concerned, I would try and generate texture with a hi-build primer, perhaps by holding the rattle can too far away and not rubbing down very much, followed by an aluminium paint....It might work?

You would never match it to the engine.....But the engine is multi-coloured any way
What do we do with the breather under there?
Currently mine exits to the air via a filter.
Same could be done but where to mount it. Unless I just leave it inside.
I wonder if they would send to the UK?
Cheers
Rev. Light