I feel your pain. Post-kid I was a 38DDD (I was a 40H-I while nursing, which was really a nightmare)...lost weight and ended up a 34DDD. My solution was breast reduction surgery, which was covered by my insurance, except for a $1k co-pay. Best thing I ever did for myself.

For some strange reason manufacturers in the UK are better about doing small band sizes and larger cup sizes, though they aren't always super cheap. I think Figleaves.com is one place where I've seen a good selection of bras in your size. I'm now a 34D and still struggle to find bras, so I can sympathize.