If you can’t spend much, this AllSaints Open Cardigan will fit the bill. It's a fail-safe choice, while not very pricey. Another strong contender for your wardrobe is this Open Cardigan. While the price of this piece is not too high, it will definitely attract a lot of attention.
If you're a bargain shopper, consider buying this AllSaints Open Cardigan. While the price is very reasonable, this product is an easy wardrobe update.