You can always redownload a package through Patch Remediation Center by right-click > Recreate Package. This is the best method as it will repull everything from Symantec for that patch.
Problem with doing it as a SWD task is that you have dont have a way to control applicability or compliance. Using the Patch engine, it does it for you via assessment scans.
Since you are not seeing the patch in the Software Delivery folder, most likely the binaries have been removed because you have the "Delete unused patches after x days" set and this patch is deemed as unused by the client.
You can always copy the file from the server to the client machine. <InstallDir>:\Program Files\Altiris\Patch Management\Packages\Updates is the location of all your downloaded updates on 7.1. The executable will be in there.
I recently rolled out SP2 for Office 2010. The way I did it was through Patch Remediation Center. I right-clicked the SP (there are 2, 1 for each architecture) and created a new policy. The target of the policy was the default software update target set on the Settings page. I then changed the schedule to "