Update.....
On my way home yesterday, I stopped into an independent tire retailer in my neighborhood. Owner is foreign..... VERY cool guy.
I tell him that I need two old tires... I explain the use. "Nothing fancy..... they are for a rolling shell..... older the better, as long as they hold air. I was thinking $10?"
He says, "$30 for the two".
I say.... "Umm..... but you are about to throw these out (he had pulled tow from a scrap heap)".
He says, "Yes, but you are screwed until you can get the car to roll. $30 for my time.... the tires are free".
At least he was honest.
$30 it is to support the local economy!
(Thank you all for your advice)