1. Preheat oven to 375° with a rack set in the middle. Make filling: In a bowl, whisk sugars, eggs, spices, salt, and pumpkin until smooth. Whisk in half-and-half.
2. Divide filling between pie shells and bake until a knife inserted in center comes out clean, 45 to 55 minutes. Let cool.
3. Make cream: Beat cream, sugar, and bourbon with a mixer until light and fluffy.
Make ahead: Chill airtight up to 1 day.
Note: Nutritional analysis is per 1/12 of pie.