You can't really mix spray paint since it's in a can. What I recommended I do 2 layers in white to prime the surface an bring I closer to neutral, then do Aspen Yellow or Gold Lumina.
Here's the metalic line.
Because the colour is translucent you might like what shade the yellow turns on the brown after 3 layers.
Also one of the 4 Ounce Bottles of Angelus Paints for $5 should be enough to cover all your gold bits.