In the wild west area there will be a few piles of gold coins (I think around 4-5) scattered around. Once picked up put them in a pot where the spawn area is then shoot the wood below the pot with a PAPed gun that has blast furnace. Then wait a few rounds until the gold had melted and the pot is full of liquid gold. Then get the Reichsrevolver from the box and interact on the pot of gold with it and re interact with it once it comes up then you will have the silver plated six shooter