If you're looking for a thrifty option, your best bet is this Topshop Beanie Hat. It's a fantastic piece, while not very costly. Another smart option is this Topshop Beret. While the price is competitive, be sure that this item will become a wonderful addition to your wardrobe.
If you're looking for a bargain, why not take a look at this Topshop Baseball Cap. While the price is very reasonable, this piece is an easy wardrobe update.