Wonder whether CPR would sell plywood, they seem to have a supply now independent from Stern's supplier. Look here: http://www.classicplayfields.com/updates.html
"We took in a major load of wood that will get us through the next five titles as mentioned above. It's really nice stuff. Two internal layers of hard maple, three layers of white ash covered with two .080" full face veneers of maritime hard rock maple. These face veneers are 25% thicker than what Stern uses on their machines and we pay for that good thick veneer on BOTH sides of the PF so it stays straight and true better than using one good grade and one lower grade."