file-roller with support for Valve Pak format
More information about file-roller in README-OLD
For ArchLinux users, there is a PKGBUILD available.
The gist also contains a PKGBUILD for python-vpk
$ mkdir build
$ cd build
$ meson ..
$ ninja
$ ninja install
Just installing this version of file-roller is not enough to make the vpk support work. For that the python vpk tool is required. It can be installed using pip:
$ sudo pip install vpk
This program is released under the terms of the GNU General Public License (GNU GPL) version 2 or greater. You can find a copy of the license in the file COPYING.