SharePoint 2013 SP1 support in Windows Server 2012 R2
Original KB number: 2891274
Before the release of Microsoft SharePoint Server 2013 Service Pack 1 (SP1), Microsoft didn't support the installation of SharePoint Server 2013 in a Windows Server 2012 R2-based environment. However, with the release of SharePoint Server 2013 SP1, this configuration is supported in Windows Server 2012 R2. You can now download SharePoint Server 2013 SP1 from the Microsoft Developer Network (MSDN), the Volume Licensing Service Center (VLSC), and the Microsoft Partner Network (MPN).
You should avoid creating your own slipstream versions because of a change in the package layout that was introduced with the March 2013 product update.