The color is metallic black.
But I would say wood will look nice. Use 1 smaller dowel and one thicker one. Cut the 3 barrels and 3 chambers. then use a slab of wood for the base. Making it open will be VERY hard if you don't know anything about prop making..But using dowels, you won't have hollowed out chambers so it won't stay shut completely. So that's impossible..If you wanted to go with PVC pipe, they are hollow but you would need to figure out how to keep it closed..Revolvers have a piece that clips into a notch, but I wouldn't even begin to know how to make it do that..
If you wanna do what the person did for that picture, it looks like they used a toy revolver and modified it..You could always note them on DA and ask them..