Unable to add Microsoft Visual C++ 2005 Redistributable (x64)

I just created an MSI with Repackager and found out that my msi doesn't capture (install) the Microsoft Visual C++ 2005 Redistributable (x64). So I find out I can add this in Installshield. I open the MSI in Installshield and click on Redistributables, but the package isn't anywhere to be found in the gallery. If I open up a fresh project, it is available to choose from... but in my MSI project, it seems I can only choose Merge Modules and not the any of the InstallShield Prerequisites.

Any ideas?

Sorry if this a dumb question... I'm new to the packaging world.