Note: In-store customers can get the same discount via this printable coupon.
A best bet is The Children's Place Skeleton Costume (pictured) for $17.47 before the coupon, $13.98 after. With free shipping, that's $21 off list and the lowest total price we could find. This set include a cap, gloves, and top and pants with glow-in-the-dark print. It's available in sizes
2/3 to 10/12 2/3 to 7/8.