If I were you, with your build, I would hit up the sporting good stores (big 5, Sports Authority) whatever you have near you and look at the 'Tankini' tops with the shorter tops (that DO show some stomach) with the razor backs. I know Speedo makes them, & like other have said: Speedo is heavy duty fabric that is sturdy and meant for swimmers. I bet you'd look amazing in one of those. You usually can buy the tops & bottoms desperately, so you can go high cut bottom or just plain bottom (what I would choose) or boy shorts bottoms (not as flattering on the straight up & down figured, IMO.
Besides that, I've had great luck with all things LL Bean!
~I have more curves than you & I just buy my swimsuits at Target from the mix & match section...putting together whatever too I like with whatever bottom works for me! Oh, what I wouldn't give to be able to go back to my cute tie on the sides bikini bottoms & teeny tiny triangle tops...but those days are Looong gone!