In a stand mixer or with a hand mixer, mix together cream cheese, pumpkin, and powdered sugar until smooth. Mix in graham cracker crumbs and pumpkin spice on medium speed until smooth and incorporated, about 2 minutes. Refrigerate the thick dough for 3-24 hours.
Line a large baking sheet with parchment paper. Set aside.
Scoop teaspoon-sized amounts of chilled dough and roll into 1-inch balls. Place on prepared baking sheet and chill for an additional 30 minutes.
Melt the chocolate in a double boiler or microwave in 30-second intervals, stirring in between until melted and smooth. Cool chocolate slightly, then remove truffles from the refrigerator.
Drop the truffles, one at a time, into the melted chocolate. Use a fork or candy dipping tool to lift the candy out, tapping gently on the side of the bowl to help excess chocolate drip off.
Place truffles back onto the baking sheet after dipping. Sprinkle with festive sprinkles immediately after dipping, or dust with pumpkin spice after chilling them to completely set the chocolate.