If you are looking to grow a pallet garden, you need not buy one.
It may take some time but you should be able to find one for free. Some places you might start looking are plant nurseries and smaller home improvement stores.
Many businesses have an abundance of pallets that they would be willing to get rid of. You just need to make sure you are selecting the right pallets.
Look at your pallet finding experience as your next adventure for your garden project. Details via: HomemadeHomeideas