Preheat the oven to 250 degrees F (120 degrees C). Line a large baking sheet with parchment paper.
Place butter into a small microwave-safe bowl and cover bowl with waxed paper. Melt in the microwave for about 40 seconds.
Combine cinnamon, brown sugar, pumpkin pie spice, and salt in a small bowl. Mix in melted butter.
Combine cereal squares, peanuts, and pumpkin seeds in a large bowl. Add butter-spice mixture and blend until well coated. Spread mixture onto prepared baking sheet.
Bake in the preheated oven for 45 minutes, stirring every 15 to 20 minutes. Remove from oven and allow to cool. Transfer to a bowl and mix in milk chocolate chips and raisins. Store in an airtight container.