Ralph Lauren offers its Ralph Lauren Home Big Pony Monogram Dog Polo Shirt in four colors (Bright Pink pictured) for $19.99 plus $5 for shipping. (Choose "economy" shipping at checkout.) That's $20 off list and the lowest total price we could find. It's available in sizes XS to L, although not in all size/color combinations. It comes with free embroidery of your pet's name.