I've drafted a letter to various bra manufacturers, enquiring into the general deficiency in D+ cup sizes. Most of the more designer brands (such as Barbara of Paris, Aubade, Simone Perele, La Perla, Janet Reger, Lepel, Lise Charmel, and so on), which produce beautiful lingerie, don't go beyond a C-cup (or occasionally a D-cup at a push), which I think is a huge shame.