Recommend not doing it, personal experience... Kids get dirty from the black rubber as the tire oxidizes, takes a lot of sand to fill the tire that will never be used, hard to get the sand out of the tire when you don't want it anymore, got to pay big bucks to get rid of the tire in the future...
how about free? I get them drop on my land every year by the wabash..
I can try to get one drug up to near the road if you want to drive all the way to fountain county..