Also the havoc launchers from chaos vehicles (see:
http://warpstoneflux.blogspot.com/2009/09/havoc-launchers.html) Although they may be a bit more in demand.
You could also get some medium-small diameter brass tubing and cut it into small lengths and bundle a couple in a frame of plasticard. That would probably be the most economical for doing 10-12.
Though, if I may ask, how are you planning to field that many cyclones?