Hi Mark,
You can find the out of the box demo binary on the FRDM-K64F Quick Start Package:

The QSP can be downloaded from this link:
http://cache.freescale.com/files/32bit/software/board_support_packages/FRDM-K64F_QSP.zip
The FRDM-K64F should come with the mass-storage device (MSD) Flash Programmer OpenSDAV2 Application preinstalled so you only need to drag and drop the out of the box demo binary file to the MBED drive:

For instructions on how to run the Out of Box Demo please follow the steps on the page 5 from the "Quick Start Guide for the Freescale Freedom Development Platform" document also found on the QSP.
Hope it helps!
Best Regards,
Carlos Mendoza
Technical Support Engineer
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