i like this swimsuit company. below is the suit i bought in a size 14. i am a 36 C cup and this supports me very well.
they are pricey, but are chlorine resistant. as a regular year round swimmer, one of these lasted me about 3 years. i'm only on my second one.
there is an option of shelf bra or soft cup. if you need the extra support as I do, the soft cup works well. i see they also have a DD suit and mastectomy suits if you browse the site.
http://www.h2owear.com/prodinfo.asp?number=SBCR
hope that helps someone out.
kb.