Talk to the local backpack shop. I asked my local owner if he could offer me a quantity discount in a similar situation, and he gave me about 40% off the price of half a dozen Hubba tents.

I made it very clear I was not asking him to sell them to me at cost; I expected him to make a profit. He was able to reduce his cost because he didn't have to factor any overhead or carrying costs of his inventory (essentially, I caught him when he was about to order, so all he had to do was get them in the back door and hand them to me at the front door the same day.) He was also willing to reduce his profit margin a bit, partly because it was a large single transaction but mostly because he's also into helping local groups get kids outdoors. So, he passed the savings along to me. We all won: it cost me less to get the tents, the kids got better tents for what they were doing, and he made a reasonable profit and built some goodwill (free advertising.)