If you're on a thrifty mission, your best bet is this Lole Beanie. It's a great item, while not very expensive. Another strong contender for your wardrobe is this Beanie. While the price of this piece is not very high, it will definitely attract a lot of attention. You may also want to look at this Quiksilver Beanie Hat. This item is not expensive either, but it will make a difference in your wardrobe.
If you're looking for something in between pricewise, you're in luck with this Sofia Cashmere Hat in stock and waiting for you. You are guaranteed to fall in love with this piece. It's also worth considering this Polo Ralph Lauren Beanie Hat. This piece is extremely popular and, just as importantly, not too pricey.
If you can afford to splurge, then you absolutely must check out this Eugenia Kim Knitted Hat. This item seems costly, but it's top quality.