The Wolfe .44 is unlocked at level 47, and the Gold Plated Revolver is unlocked at 5th prestige! You could wait, to unlock it, but there's a much easier way.
If you happened to pre-order the game than your in luck. You'll have a code that gives you early access to the game mode Classic Conflict. If you didn't preorder, the code should be floating around somewhere on the net. In Classic Conflict everyone gets to pick and play as a James Bond villain. The character GoldFinger actually starts with the Gold Plated Revolver as a secondary. So you and a friend can just boost this on the side of a map. Your friend will want to pick a character that does not get any extra health, and you'll want to headshot your friend so that it actually kills them in one hit. Remember not to reload the Gold Revolver. The Gold Revolver has 7 shots, so you can afford to miss once.
If you didn't pre-order the game, and don't have access to Classic Conflict, than a friend who does have it can just invite you in.
If you did pre-order the game, make sure you actually used your code!