Roger,
What you need to do comes down to creating a small ANT script that will make a copy of the features you want on a computer with internet access. You will need to know the feature IDs, versions, and update site URLs with those features. This information is available from, among other place, the install new software dialog for the features you select and decide you want to install. To get you started, I've created an example ANT script that mirrors some of the content you mentioned (the formatting was messed up in the cut-and-paste btw):
<?xml version="1.0" encoding="UTF-8"?>
<project name="Create local mirror" default="run" >
<target name="run" >
<p2.mirror>
<repository location="file:localmirror" name="localmirror" />
<source>
<repository location="http://software-dl.ti.com/dsps/dsps_public_sw/sdo_ccstudio/msp430/Updates/p2win32/" />
<repository location="http://software-dl.ti.com/dsps/dsps_public_sw/sdo_ccstudio/codegen/Updates/p2win32/" />
<repository location="http://software-dl.ti.com/dsps/dsps_public_sw/sdo_ccstudio/TargetContent/Updates/full/" />
<repository location="http://software-dl.ti.com/dsps/dsps_public_sw/sdo_ccstudio/CCSv5.1/Updates/Emulation/win32/full/" />
</source>
<iu id="com.ti.cgt.msp430.4.2.win32.feature.group" version="4.2.4" />
<iu id="com.ti.cgt.tms470.5.1.win32.feature.group" version="5.1.5" />
<iu id="com.ti.ccstudio.msp430.emu.win32.feature.group" version="5.5.0.22" />
<iu id="com.ti.grace.win32.feature.group" version="2.20.2.32" />
<iu id="com.ti.emulation.pack.win32.feature.group" version="5.1.450.0" />
</p2.mirror>
</target>
</project>
Put this script in a file called "mirror.xml", and then run it by running a command like:
%ECLIPSE_INSTALL%\eclipsec --launcher.suppressErrors -nosplash -application org.eclipse.ant.core.antRunner -buildfile mirror.xml
Where %ECLIPSE_INSTALL% is the path to a local eclipse or CCS installation.
Once you have the local folder, you can install these components by adding the local path using the install new software->Add->local menu.