Where can I find the background from Wordpress theme Eventerra?


I am new here and I am not sure that thes is the correct topic for this, but I will try anyway.

For a website I have purchased Eventerra, and that is working quite well. Now I need to design some items for this conference and I would like to use the blue background for posters and badges. Can I find this some where or purchase? Hope that someone can help me on this.

best regards,