1/2 cup finely ground graham crackers (from 4 crackers)
1 1/2 tablespoons unsalted butter, melted
Preheat oven to 325 degrees. Make the cheesecakes: Beat cream cheese with a mixer on medium speed until smooth. Add sugar. Beat on medium speed for 3 minutes more. Reduce speed to low. Add eggs, 1 at a time, beating well after each addition. Raise speed to medium. Add sour cream, lemon juice, and 1/4 teaspoon salt. Beat for 3 minutes.
Divide batter among six 6-ounce jars, filling each two-thirds full. Transfer jars to a deep baking dish; add enough boiling water to dish to reach halfway up the sides of the jars. Cover dish with foil; cut 8 slits into top to vent. Bake until set in the center, about 25 minutes. Let cool. Refrigerate overnight to set.
Meanwhile, make the graham topping: Stir together graham-cracker crumbs and butter. Bake on a parchment-lined baking sheet for 10 minutes. Let cool.
Top each cheesecake with 1 tablespoon plus 1 1/2 teaspoons preserves. Divide graham topping among jars (about 1 heaping tablespoon each).
Cakes can be refrigerated for up to 4 days. Topping can be stored at room temperature for up to 1 week.