If you're not planning on spending much, this Open Cardigan will fit the bill. It's a great choice, while not very costly. Another strong contender for your wardrobe is this Leith Open Cardigan. While the price of this item is not very high, it will certainly attract a lot of attention. You may also want to look at this Painted Threads Open Cardigan. 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 Open Cardigan in stock and waiting for you. You are guaranteed to fall in love with this item.
If you're on a hunt for a luxury item, then what you're looking for is this Marni Open Cardigan. It's more expensive but worth your money.