Amuse Studios has a color called Pistachio here:
https://www.amusestudio.com/Order.as...ispSubCatID=13
but is only colored on one side, the other side is white.
Bazzill Basics has a new color called French Mints: item # 5-5155. You can see it on their site here:
Green Cardstock | Bazzill Basics Paper
Bazzill is usually sold in big box craft stores like Hobby Lobby or Michaels.
And I also found this online place:
Mint Card Stock - 12 x 12 in 65 lb Cover Felt | CutMates Card Stock 3-CUT008 They have a Mint color as well as one called Creme De Menthe that might be nice. I've never ordered from this place so I can't speak to the weight or quality of their papers.
Hope this helps!