My local Timber merchants can order it in for me. If you have a local Timber merchants it may be worth asking if they provide a similar service. Because veneer MDF is not your run of the mill everyday sales they are not usually stocked by most Timber yards. The service is usually quite good, most of the time with a next day delivery.
The benefits are that if the faces are damaged it is easier to refuse the delivery or have them sent back.
Just a thought