Line a rimmed baking sheet with parchment paper and make sure it fits flat in your freezer. Soften the cream cheese on the counter for 30 to 45 minutes.
Pulse about 14 full graham cracker sheets in a food processor until fine and sandy, then measure out 2 cups plus 2 tablespoons. Alternatively, crush them in a zip-top bag with a rolling pin.
Beat the softened cream cheese in a large mixing bowl on medium speed for 1 to 2 minutes until completely smooth, scraping down the sides and bottom of the bowl.
Add the pumpkin puree, powdered sugar, pumpkin pie spice, vanilla, and sea salt. Beat on low for 30 seconds, then on medium for another minute until silky and evenly orange; scrape the bowl and adjust spice to taste.
Fold the 2 cups of graham cracker crumbs into the filling with a rubber spatula until no dry streaks remain; the mixture will be soft and sticky but firms up as it chills.
Cover the bowl tightly and refrigerate for at least 1 hour, or until firm enough to hold its shape when scooped. It can chill overnight.
Use a 1 1/2 tablespoon cookie scoop to portion 24 mounds, then roll each into a smooth ball between your palms and place on the parchment-lined baking sheet.
Freeze the balls for 15 to 20 minutes until firm to the touch but not frozen solid, so they hold together when dipped.
Microwave the white chocolate wafers and coconut oil in a deep, narrow bowl at 50 percent power in 15 to 20 second bursts, stirring each time, until smooth and fluid. Stir the reserved 2 tablespoons graham cracker crumbs with the cinnamon for the topping.
Working with about 6 balls at a time and keeping the rest cold, roll each in the melted chocolate, lift on a fork, tap off the excess, and slide back onto the parchment.
While the chocolate is still wet, sprinkle each ball with cinnamon graham crumbs and fall sprinkles if desired, then refrigerate for about 15 minutes until the shell is firm.