I think I would go with a chocolate dress and a blue sash. It's not a colour I have ever seen at a wedding either but I have seen it a lot in interior design and I do remember having a lovely chocolate brown top with baby blue straps years ago that I wore to death. Did you try dessy for pics of dresses, they usually have a good mix.
You might get some inspiration. I'd go for blue with a brown sash. But that's because I'm not a fan of brown. the GM in brown suits with an aqua cravat or tie might be nice.
I have come across quite a bit of chocolate and teal while researching my invites. For your stationary check out