I saw this set on ebay:

Looks like that guy has a whole bunch of them an similar ones. From the looks of it, its a bunch of small plastic pieces(mostly squares) that you can assmble in various ways.. and its dirt cheap.

I don't see it for sale anywhere is, some I'm guess its somethign this guy is making. Does anyone have experience with this kit? I want to throw a seige tourney (using blood and the badlands rules) and need another castle or two...