I also use rolls of thin foam to line the interior of my arm and leg parts. It makes the armor more comfortable and helps keep it from traveling while you're wearing it.
you can buy motorcycle helmet padding thats all put together but i dont know if it will fit, you could always buy some sponges though hehehe. I think sponges would work fine.
yeah i sto......borrowed a bunch of motorcycle cataloges from my art teacher and they have padding for sale in them, and some awesome under armor, and of course visors, mabey i should scan some of them and upload them.