Sure, you can buy trail mix, but it's easy (and cheaper) to make your own. Take a trip down the bulk aisle and choose a fun mix of nuts, seeds, and dried fruit.
Preheat the oven to 350°. Line a rimmed baking sheet with parchment paper. In a large bowl, toss the hazelnuts, pepitas, walnuts, coconut oil, and kosher salt until coated; spread out evenly on the baking sheet. Bake, stirring once, until the mix is toasted, about 10 minutes. Let cool completely. Mix in the chocolate and blueberries. Transfer to an airtight container.