What to do when GP wont provide health certificates on NHS or for private fee?

[telford]

Want to do tandem skydive for charity, ironically for a childrens intensive care ward, but need GP to sign form 115 to say even though over 40 no unacceptable health risks. Understand would likely have to pay a fee but surgery refuses to do this either as a NHS or private patient as say their Doctors don't do this. Form says has to be someone with access to my records...my GP surgery! What am I supposed to do now? Even CCG agrees it has to be GP but nobody can persuade them to do this...advice from surgery is to go online and find someone...like who, they need access to my history.