This is a very difficult question to answer without any photos and measurements. Everyone is different and you just cant say that a 475 cc implant will be a DD or a D cup in you or anyone else.
You need to go for the look you are going for rather a particular cup size. Besides you will go to one store and they will size you one way and go to another and they will size your differently. So trying to achieve a look is far more consistant that going after a cup size. Having said that you can play around with home made implants out of rice and stockings; I call it the Rice Test. You can learn how to do this on my website journal posts.
Good luck. Make sure you see a board certified plastic surgeon.



