I visited CC Station about three months after the first book was released in the U.S. (oh, to be a wee lass once again!), and they did not yet have the half-disappeared cart available. However, being British and prescient, the conductors had taken it upon themselves to paint a plank of wood with "Platform 9 3/4," which was available upon request to hold while standing between platforms nine and ten. Though completely unofficial, it was bliss.
That is brilliant! I'll make it there again one day to see 9 3/4!