Jeatyn
You're entitled to see any doctor at the practice that you want to see, so you could always try and see a different doctor and see if they're more helpful. You don't have to give a reason, just make an appointment with someone else at the surgery.
If that's no good, you are entitled to change your GP practice without giving a reason. Even if all the other practices in the area are full you can change by contacting your local PCT and asking them to allocate you to a new surgery. Details of how to do this are
here. There's also information there on how to complain about your GP if you feel like taking it further, though I'd recommend you move to a different GP before starting complaint procedures.
Whereabouts are you based btw? I might be able to point you in the direction of a trans-friendly GP if you're anywhere that I have mates or other contacts - feel free to PM me if you don't want to post the info.
Incidentally, it's also illegal in the UK for a PCT to have a blanket ban on funding trans related treatment, so your GP is talking out of his backside about that also. He may be confused in that you might have to go to London to receive treatment - i.e. to Charing Cross Gender Identity Clinic (aka CX) - but that doesn't mean there's no funding for patients from outside of London!
Also, there's no point in asking for a referral to an endo. If your PCT has the contract with CX then you'll have to see a local psych first who will then refer you to CX - you can't bypass that by getting a referral to an endo and just walk away with T in the UK I'm afraid.
If I can help at all, feel free to get in touch mate.