If you can’t spend much, your best bet is this Bebe Open Cardigan. It's a popular product, while not very expensive. Another good option is this Lou & Grey Open Cardigan. While the price is not too high, be sure that this piece will become a worthy addition to your wardrobe. You might also want to consider this Open Cardigan. The price is very reasonable, but the effect on your wardrobe will be pretty fantastic.