One recipe I found had the following ingredients.
2 cups pumpkin puree 1 cup heavy cream 1/2 cup milk 4 eggs 3/4 to 1 cup granulated sugar, according to taste 1 1/2 teaspoons ground ginger 1/4 teaspoon ground coriander seed 1/2 cup finely chopped crystallized ginger
This does not include the crust witch would have several more ingredients. There are many ways of making pumpkin pie with various different ingredients.
175 g (6ozs.) Short pastry roll out and line a 230mm (9inch) pie dish
1 cup cooked mashed pumpkin
half a cup of brown sugar
half a teaspoon of salt
half a teaspoon of cinnamon
half a teaspoon mixed spice
quarter teaspoon nutmeg
3 quarters of a cup of milk
Mix or beat filling ingredients thoroughly adding milk
last. Pour into pastry shell and bake 20 mins at 220
degrees celsius (425 degrees F) Then about 30 mins at 180 degrees C (350 degrees F) till filling is set.