thanks namelus. It looks like Home Depot just started selling a 1 shot one, via the web.
I bought a sewing kit to make a sock heating pad. But the needles were gosh darn too tiny.
Zipties to the rescue. I purchased low cut socks from the dollar store. I cut a slit in the collar and worked the narrow zip tie around. Filled it with rice. I pulled the tie tight and cut off the access. Viola it worked just dandy