What an amazing rack! Let's see - a DDD would be the same as an F-cup, and that looks about right to me.
I've looked at the scan up close in Photoshop and I don't see any artifacts of morphing at all. The detail in the fabric of her swimsuit top is unbroken and undistorted. There ARE real women out there with actual big breasts... it ain't ALL morphing! 
My bet is they're natural, too! (Boom ba-=ba, boom ba-ba...)