In a large mixing bowl, combine the Rice Chex cereal, M&M's, dried cranberries, and pretzel sticks. Gently toss to mix all the ingredients evenly.
In a microwave-safe bowl, melt the white chocolate chips with the vegetable oil in 30-second intervals, stirring in between until smooth.
Drizzle the melted white chocolate over the snack mix and gently stir to coat the mixture evenly.
Spread the coated snack mix onto a large baking sheet lined with parchment paper.
Sprinkle the sea salt over the top of the snack mix. Let it cool completely until the chocolate hardens, about 30 minutes.
Once cooled, break apart any clumps and transfer the snack mix to an airtight container for storage.