Since Apple no longer lists Mavericks on the primary Mac App Store search, you may need to use these verified external repositories:
Offers specific build versions (e.g., 13F34) for legacy collectors on the Macintosh Repository site. mac os x mavericks 10.9 iso and dmg image download
The Apple Support Downloads page provides the 10.9.5 Combo Update (approx. 982 MB) to upgrade an existing 10.9 system. Full ISO/DMG Images: Since Apple no longer lists Mavericks on the
Today, users primarily seek of Mavericks for legacy hardware restoration, virtual machine testing (like VMware or VirtualBox), or creating bootable installation media. Quick Download Links for Mavericks 10.9 mac os x mavericks 10.9 iso and dmg image download
Advanced users can use a terminal script from Mavericks Forever to fetch installer images directly.
Hosted as a 5.7 GB optical disc image, available at the Internet Archive (10.9.5) .