You may be surprised to know the diet program Atkins makes peanut butter cups. Their ingredients are not 100% ok, since the main focus seems to be less carbs. Also if you want an alternative to M&M's you should try their peanut candies, they're really good. You can can buy them on Amazon.
Atkins Peanut Candies with Forgotten Ice Cream and Let's Do Organic ice cream cones.
3. Unreal Peanut Butter Cups
These are my favorite, because I love the smaller company brands. They taste good too.
Fair Trade USA certified
some are vegan
4. Newman's Organic
I haven't tried them yet, but am listing them in case anyone wishes to do so.