I was contracted to make a header design a few days ago for a clan site that plays Call of Duty, Battlefield and another game - I forget... The client has yet to respond back though
I know your request is for a free header - so I don't know if you'd be interested in purchasing the following design:
See true size preview here...
I'm happy to make revisions so that the design fits directly into your forum design and at a good price. PM me if interested. Otherwise - good luck with your request
J.