Virgin Galactic has licensed a set of “Limited Edition” models of the WhiteKnightTwo and SpaceShipTwo combo. They are available in 1/400 and 1/200 scale die-cast models at B4 YOUR FLIGHT.
Don’t see any SpaceShipTwo models at Amazon yet but there are several SpaceShipOne models, e.g.
They seem to be out of stock. I hope they will have them back in stock again.