GSG 5 P, Comes with a extra railed forearm w\rail covers, 22 round mag, sling mount end cap, hogue grip & ($70) threaded adapter for suppressor (3 lug or threaded ) Plus a box of Remington HP 525 bulk pack. $400.
http://www.mygsg5.com/GSG-5PAdapters.htm
http://www.cobraairsoft.com/product_info.php?manufacturers_id=35&products_id=3236
http://www.mygsg5.com/GSG-5PAdapters.htm
http://www.cobraairsoft.com/product_info.php?manufacturers_id=35&products_id=3236