sounds too specific to be scrap hounds, i normally find copper and lead get better money than steel (here in the UK) sounds to me like they were stolen to order.
I would check
www.milweb.net and see if anyone has posted up items
alot of military hardware gets put on there from all over the Globe so its worth watchin.....if you email the admin for the forum he can keep and eye out for you (rather than post up stolen bits which will inevetebly spook any theif into melting it down)
Richard