I recently got 2 Panache Cleo bras NWT for approximately $27 each, including shipping, from EBAY-UK. One was last summers pattern the other last fall but for the price I didn't care. They were returnable but I already had the bras so I knew they would fit. Ebay US was 2x the price as the UK Ebay.
Lots of cheap bras, new and used, are available on a subreddit called Braswap and also on Bratabase. Bratabase is neat because women measure their bras, include their own measurements and give information on how the bra fits. For fittings and general bra advice there is a subreddit called A Bra That Fits. It's a great resource for anything bras.

