So, I found this great site which offers free textures to be used in your games, both commercial and non-commercial.
Only thing you can not do with these textures is to sell the textures themselves. But you're free to sell games that use these textures.
These textures will be great to be used in Sabre when it's ready.
The link:
Texturemate
Check this page (the texturemate FAQ part) if you want to read the rules by yourself: http://texturemate.com/content/about
