Apacer made a cd burner/memory card reader that used AA batteries that a friend used with great success.
http://www.apacer.com/en/products/Mu...ia_Storage.htm
I think he had the CP100, maybe Cp200.... can't remember.
Prices of blank CD's are pretty cheap, and seeing they do a DVD version, that might be the one to have.
He did end burning a few discs for other people on the trip, so factor that in, maybee it could pay for you batteries and discs?