mypaint-data-extras binary package in Ubuntu Mantic amd64

 MyPaint is a pressure- and tilt-sensitive painting program which works well
 with Wacom graphics tablets and other similar devices. It comes with a large
 brush collection including charcoal and ink to emulate real media, but the
 highly configurable brush engine allows you to experiment with your own
 brushes and with not-quite-natural painting.
 .
 This package contains high resolution paper texture backgrounds for painting
 on. Since the files are large, installation is optional.

Source package