I have begun a collection. We now have 4 large rolling pins and 2 wooden batik blocks. We have 8 lengths of coated copper wire. Room for more, certainly, but a good place to begin.
It would seem from observing the roll out of this little collection that clay once reduced to slip, all watery and silty, feels best when spread evenly and rubbed in over the large worn wooden disk. And while I imagined that the children would use the wires as another design element for prints, these were obviously better served as connecting wires for ornately printed and ridged clay machines.