They make video card and motherboards (and various other system component cards) in different colors all the time simply for design considerations ... Some companies think of it as part of their identifying trademark, while others make multiple color options available in order to market their wares to a newer generation of computer mod builders who like to color coordinate and show off the interiors of their computers.
The orange/golden brown one I haven't seen before ... black is certainly one that is available through PSI that I don't see displayed here. Blue is also available through PSI.
In order to thin these down enough that the blank maker can wrap them round a brass barrel and cast, they are typically sanded down from the reverse (no component side), as the component side is much more interesting looking. The small flat surface mounted components are typically left in place, while the larger components and pins are usually removed, as they can get in the way. It is somewhat unusual to hear of pins being left behind, but as they are made of a mild steel they don't get too much in the way. Make sure you seal them in CA for your finish, though, as this steel is NOT stainless or corrosion resistant ... you will see rust spots.