Target? Kohl's?
I know when I worked at Macy's we had people come in and do the same thing. I used to have to authorize rather massive discounts for large quantities all the time. Not that we could ever get that qty for $20 each, but just saying. it might be worth approaching a store manager (like Kohl's or Target) and seeing what they will do.
Otherwise I can get 30% off zappos.com, but that doesn't really help with your time frame.