Patrick,
Back again mate, Just found some info on the plastic stuff.
It`s called POLYMORPH and is available on that "e#@y" auction site.
You`ll find it listed as item number 280611194302...
Check out the add, it costs about $15au with postage for 300gms, and thats quite enough to do a heap of casts, as it is reusable.
Hope this is of some help,
Cheers,
Roger