Where to buy sweater too match with dress?

I'm looking for a light blue sweater to wear with my white dress. One thats a lightish darkish sky blue thats elbo length and short so it would look good on a dress. I've looked at Nordstrom and macys but they only have a greenish bluish tuquose color that wouldnt look good on me. Any other suggestions plz where to buy one??? a store that has a bunch of sweaters with a ton of different varieties of colors maybe??? thnx!