There's no need. SP2 should be cumulative. But, if you really want, it's still available for download on Microsoft's website. The lack of support just means that all future security patches for Vista will require SP2, and if you call MS for support, you will have to have SP2. It doesn't mean they remove all downloads for SP1. You can still probably find the Win95a update on Microsoft's website if you really want.
I've recently recovered my system (Home Premium 32 bit)using recovery disks. I need to apply SP1 (single computer) and SP2. Where can I find a copy of SP1 now that Microsoft no longer supports it?

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