There is no RAS 2013, CR for Visual Studio is the SDK and inProc RAS for CR 2013.
If you are using CRSE 2013 then you need the BI 4.1 .NET SDK package which you can get from Service Market Place under your OEM Contract.
If using standard Crystal Reports then go here to get the installer:
SAP Crystal Reports, developer version for Microsoft Visual Studio: Updates & Runtime Downloads
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