Hey I just spotted a sales thread with two real good high-humidity riparium plants: 1 Anubias nana 'Petite' (for trellis raft) 2. Cryptocoryne wendtii 'Green Gecko' (for hanging planter).
'Green Gecko' is really attractive when grown emersed. The seller was offering them in big lots. I don't know if they would be willing to break them down some more(?).