Amazon offers Prime members the LeapFrog LeapReader Deluxe Writing Workbook: "Learn to Write Letters with Mr. Pencils" for $9 with free shipping. (Non-members can spend $35 to bag free shipping; otherwise, it adds $6.48.) That's the lowest total price we could find by $8. It features a 20-page story with 45 activities and 400 interactive responses. It works with LeapReader system (not included).
Orders placed by December 19 are guaranteed to arrive by Christmas.