Some enthusiasts maintain private archives. For example, a large collection of BlackBerry firmware can be found in this community-maintained Google Drive folder.
Once you have located a firmware link and downloaded the .exe file (the "handheld software"), follow these steps to flash your device: TechCrunch blackberry 9630 firmware link
Sites like Lunar Project and BBViet.info are frequently recommended by the BlackBerry community on Reddit for legacy OS files. Some enthusiasts maintain private archives