The idea for practical gift. Sleigh could be a gift in itself or it could be a packaging for little presents/sweets.
External dimensions: 25x11 cm, total height 15 cm;
internal dimensions of a box: 15x10 cm, height ~8 cm
Simply in making model, use a dash of a glue to connect each of pieces. It is better to decorate internal elements before gluing and external after.