Exhaust Flange

My 63 station bus recently blew the exhaust flange gasket. I bought another gasket to replace it. Once I loosened and removed the exhaust pipe from the manifold, I noticed that the old gasket wasn't really a gasket. It looked more like a donut. I installed the new gasket and noticed that the gasket still had a lot of play in it and leaked like all hell.
Is there a donut gasket for the exhaust flange and if so what size would it be?
Thanks,
Troy

There are 2 style exhausts on Econos,earlier used a flat gasket which pretty much sucked,later a donut gasket. You obviously have the wrong gasket. Just measure the pipe to determine size. I dont know the size off top of my head.