Shelley and I went shopping last night and here were our two favs:
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http://www.dessy.com/dresses/bridesmaid/2832/
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http://www.jlmcouture.com/Jim-Hjelm-Occasions/Bridesmaid/Additional/Style-5033
I am getting price quotes from netbride.com
So far there are two votes for the one-shouldered version!