Download them at bt.easytree.org, and burn them yourself. No money is passed to Pink Floyd or the copyright holders from the purchase of these DVDs. Many of these are compiled by fans, for fans without profit. Buy a DVD burner for $50 if you need to, it's worth it in the long run.

If you're not up for downloading, look into trading groups and see if anyone will swap these for DVD blanks or other bootlegs you have to trade. Look into disc trading policies, and check out places like this:
http://groups.yahoo.com/group/harvested-weeds/

The discs described here sound awfully close to those released by Harvested.

http://www.harvested.org/