If you have a valid 2013 license key, you might find a mirror of the setup on third-party archives, but it is technically against Acronis’s EULA. If you do not have a key, the software is not free.
If you own a license for Acronis True Image (or have an archive of the installer for version 2013), you can legitimately create your own "setup free" bootable media. This is the safest and most reliable way to use the software without installing it on a target machine. Acronis True Image Home 2013 16.0 Build 6514 setup free
For everyone else: Let this software rest in peace (2009–2018). Move to modern backup tools today. If you have a valid 2013 license key,
Disclaimer: This post is for educational and legacy support purposes. Always use legal, licensed software. The author is not responsible for data loss caused by outdated drivers. This is the safest and most reliable way