seems during hunting season you can buy 'deer corn' to use for these...at walmarts in the hunting equipment area in 40lb bags for about $4. dont know how accurate that still is on price etc.
could be a good project to do for various shape xmas presents. i've got one dd gave me last yr for xmas and use it mostly here at the puter but i could use a better design...maybe one that fits under my right forearm with filler in the underside and a quilted top for use in winter to keep top of arm warm, with a thumbhole to keep the top side in place, sorry just thunk'n outloud again. fwiw, jeanne