This is my last balsa order. I get all of my balsa from National Balsa and all my aircraft ply and spruce from Aircraft Spruce. Aircraft spruce is about 20% less than national balsa for aircraft ply, but you have to get it in 2x4 sheets Shipping works out about $20 for a 2x4 sheet of ply, so its beneficial to order 4 or 5 sheets at a time. I also only order 6" wide sheets. All of this is for one model: