Microsoft Dynamics NAV 2013 is a landmark release, building on a strong product foundation to deliver new levels of customer and partner value through faster, more efficient implementations, compelling new and enhanced application functionality, and unparalleled levels of customer choice on how to deploy and access the solution.

You can find the download here https://mbs.microsoft.com/partnersource/support/selfsupport/productreleases/MSDYN_NAV2013RTMDownload?r=18&l=11

Regards,

Max Beuker