Activity for Heather

This is the wedding dress I want. I know it. But I cannot find it anywhere. Can anyone help? (I'm fine with similar ones) http://media-cache-lt0.pinterest.com/upload/214132157253423855_m6HBIhYv_f.jpg

I want to be able to buy the dresses for my girls and because of that I'd like to keep them under $50 each. Where are some really great places to find dresses? Or do you have any suggestions? I want blush/ivory/rose (one of those) and for them...