I would look for a used TNF or maybe Sierra Designs synthetic bag. Look on Craigslist. Prices tend to be better than eBay. Not everyone on Craigslist will be willing to ship to you,but some will. A free program called Craigslist Reader will scan any city you want. I'm using it to look for a bag right now.

I would stay away from a brand I don't recognize. Look through the sponsors ads and see what they are selling. STP has an inexpensive Marmot bag for sale-
http://www.sierratradingpost.com/sleeping-bags~d~208/?page=1
_________________________
Don't get me started, you know how I get.