McMasters have bulk brake/clutch lining by the sheet or strip (http://www.mcmaster.com/#) I am thinking possiably a better and less expensive way may be to check clutch lining on ebay, their are several tractor lining sets available, possiably something would be of your clutch dimentions?
Where Are You From? Leavenworth, WA / Yuma, AZ
Do You own a car built by Durant? A-22 / model 40 / Flint