stone soup

This is a cooking stone used for chuckwagon cooking around the turn of the century. The stones were heated in the campfire and then placed in a metal lined oak box, just bigger than the diameter of the stone. One stone went on the bottom, then the pot, then another stone on top. The cover on the box was latched down and the meal cooked as the cattle drive moved to the next location. 

I've been asked to forge a new tool to replace the missing hook. A design similar to a steak turner almost works, but because the box is narrow, the hook has to be slightly different shape. It's easy enough to make something that works, but I'd like it to be as close a reproduction as possible.  Anyone seen one of these before?