If you're on a thrifty budget, your best bet is this Topshop Jacket. It's a great piece, while not very expensive. In this price range, you can also look at this Topshop Blazer. It's also a popular item and won't break the bank.
If you're a bargain shopper, take a look at this Topshop Blazer. While the price is very reasonable, this piece is an easy wardrobe update.