Did you think the jewellery section of the retail giant is not for a grimdark hobbyist like you? Think again! If you search for steampunk gears you may find top quality bits that can be purchased cheaply by the bagful.
Black is one of the challenging colours as how you add darker shades to something that is technically as dark as things go? Fortunately real world objects are not perfect quantum black bodies and are actually grey so the trick is to find a shade of grey that will make our brains think its black. For me it's Vallejo 306 Dark Rubber from the Panzer Aces line. »