Dwight,
The stuff I have is called "Super Dri-Aid" tm
Distributed by:
Hal-Hen Company, Inc
Long Island, NY 11106
The pellets are listed as Non-toxic. Don't remember the price as I got them about 20 years ago, but you would need a few jars of them since the original size is for a pair of Hearing Aids.
Hope this helps.
You can check with an aircraft repair shop or some auto shops. Aircraft cylinders come packed with rather large dessicant packs to prevent rust in the cylinder walls, I have used these in fiddle cases for outdoor travel. I have also used these in tool box drawers to help with tools rusting. They usually throw them away, so probably available at no cost. Just another option.
I think they usually are, but the little ones I had started coming apart at the seams when I heated them. So, the moisture went out, but then I had a bunch of little pebbles everywhere.
The Super Dri-Aid pellets are about 1/8 inch dia. come in jars. Just spread out on a microwave plate, heat, let cool in micro. Place between foam with Accordion on top and close box so it is air tight.
Looks like the rice thing worked. I'll keep this other in mind. There's another thing out there, a canister about the size of a bar of soap. Changes color when it needs to be recharged.
Rice is cheap though. If it changes color, not quite sure what I should do with it, but I think eating is not one of them.