Amazon offers Prime members the Skylanders SWAP Force Starter Pack for PS4 for $19.95 with free shipping. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping adds $4.98.) That's the lowest total price we could find by $4. This pack includes the video game, a Portal of Power, three Skylanders figures, a character poster, three sticker sheets with secret codes, and three trading cards.
Orders placed via 2-day shipping by December 22 will arrive in time for Christmas. (This option is free for Prime members, but an extra $7.98 for everyone else.)