Grenade and Claymore are cheap in this nerf parts site.
http://www.nfstrike.com/p/CLAYMORE-Electric-Remote-Control-Water-Beads-Clip-Water-Bullet-Ball-Bomb-Outdoor-CS-Equipment-Green_2335510.html
http://www.nfstrike.com/p/Tactical-Plastic-Modified-Crystal-Water-Beads-Bomb-Crystal-Water-Bullet-Bomb-Black-Orange_2334418.html
extra coupon:NFSTRIKE1