The black rubber/foam top parts of the m203 I got from Evike.com, a air soft store. ( 12 ) tops for $ 15.00. The 10 silver bottom shells I found at a flea market here in Fla. for $ 20.00, he is out of them now, but will let me know when he gets any more. The 12g shotgun shells came from a guy i live near, ( 500 ) shells I have setting by my door. The copper & silver rounds are from a nerf gun i have. The one silver 7 black emile grenade is just some pvc pipe, and
some foamies cut, and painted. Hope this helps.
P.S. Sun or Mon, i'll try to make a mold, cast a few, and see how they come out.