This card basically is the strongest card in your deck. Get a Witch and get this, and you've got a deck that is functionally extremely similar to a deck that has two Witches in it. The only time it isn't a Witch is when you draw it in the same hand as your Witch, and in that case it's BETTER than a Witch, because...
(1) If the card had ACTUALLY been a Witch, they would have collided, and you'd only be able to play one anyway.
(2) But with your card instead, you can name Silver or Gold, THEN play the Witch.
(3) When the Curses run out, your card can draw something else instead of Witch, so you've only got half the near-useless Action cards than you'd have had if you'd bought two Witches instead.
In other words, if you've got a Witch in your hand, your card is strictly superior (caveat: usual puzzle edge cases apply) to a second Witch.
More to the point, buying one of these is strictly superior (c: upeca) to every card in your deck.
I really think the card is broken at any cost. $8 wouldn't be broken, I suppose, but nor would it be very fun.