I wear a 40 D or DD (depending on the bra and the time of month). I've been buying Champion sports bras for the last three years - they're made in the USA. I may have to forgo my local manufacture ethos and get something a little more supportive than a compression style sports bra. There are several available that have real cups that look like good choices. If I get something new I'll report back on how it works out!

I've built tanks and tops with shelf bras in them, and I've made corsets - but I haven't ever tackled anything with cups so I don't think I"ll be trying to make my own any time soon....