Biggest smallblock?

Indy is offering a 472 crate small block. 4.2" bore and a 4.25" stroke. The siamese bore blocks will take a 4.2" bore and probably will go to 4.25" but there isn't a head gasket for that bore size. Yet. The Blowtie people are pushing 500 inches with a tall deck aftermarket block that has a 9.6" deck height which is our stock height. Frustrating ain't it?