"you've been told before we don't offer v3 support if you want support upgrade to v4, don't ask again"
Is that an actual, exact quote? If so, then they've got bigger problems than the pricing.
You can get away with quite obscene pricing if you act courteously, respond fast to inquiries, outdo just about every competitor when it comes to professionalism etc.
Just a quick name that comes to mind would be Rackspace with their brand built around their "Fanatical Support" trademark.