single leaves? the java fern I've ever purchased was in whole plant form, usually for around 6-10$ for a good sized clump but if you know anyone with any in their tanks they are usually MORE than willing to give big clumps away. In my 55g tank I throw out a 5g bucket worth of plant clippings every couple of months, much of it is javafern and java moss.
This little runner shouldn't cost more than 5$ or so at a pet store
