Finishing first on the Christmas Event 2019 gift-giving leaderboard was the only way to get this Unique gun, so it is no longer obtainable and there is no set it belongs to. The gold finish is what players notice first, but the real pull is that only a few exist and price is set in private deals.
Questions players ask
How much is Gold Minty worth?
There is no stable price: trophies rarely change hands and deals happen privately. The number on value lists is symbolic.
Can you still get Gold Minty?
No. It was awarded for a leaderboard place in an event and is not given out again.