Good luck not spending a fortune! You can try ebay or craigslist, they show up there on occasion. I just did a quick check of ebay and it was interesting to see many many inexpensive 20 lb stuffers for very reasonable prices, however, step up to 30 and the cost goes waaaay up!
You might also try this site which was recommended to me by another user:
http://www.bid-on-equipment.com/default.htm