Fill a small saucepan halfway with water. Add 1 tablespoon pumpkin pie spice, 1/2 teaspoon Worcestershire sauce, and 1/2 teaspoon sea salt and bring to a boil.
Reduce heat to medium-high and add pumpkin seeds to the saucepan. Simmer, stirring occasionally, about 20 minutes. Remove from heat, drain the seeds, and transfer to a medium-sized bowl.
Preheat the oven to 250 degrees F (120 degrees C). Grease a 1-inch deep baking sheet.
Mix remaining pumpkin pie spice, Worcestershire sauce, and sea salt with melted butter in a bowl. Pour spiced butter into the bowl with the boiled pumpkin seeds and stir until evenly coated. Pour seeds onto the prepared baking sheet and sprinkle evenly with additional sea salt.
Bake in the preheated oven until browned, about 2 hours, stirring every half hour.
Remove seeds from oven and enjoy hot or at room temperature. Store in an airtight container.