[WTB G&P 9mm SMG]

Best bet is to buy a new one from China or Taiwan bud. THey're quite a specialist thing so if somebody has one they aren't going to be selling it. airsoftglobal still have a load of trademarked receivers if you start there
http://www.airsoftglobal.com/shop/index.php?main_page=product_info&cPath=32_222&products_id=2322

[M16 VN (short) Midcaps wanted]

http://uk.redwolfairsoft.com/redwolf/airsoft/Magazines_MAG_AEG_MAG_M16_Mid_Cap_130rds_VN_style_Magazine_Box_Set_7pcs_Box.htm

not metal bodied but very durable and high quality. Affordable too