I used half a terry when Natty was in little ones. Terry is very bulky and not very absorbent, so it's limited in that way.
Check out the cloth nappy making threads - someone in there may be able to give you a tip as to where to get bamboo online. (I don't think it's cheap anywhere particularly.)
I ordered 3 large ones for Natty! We got a cow hide, pink cammo and red rose. Thanks so much for the tip!!!