AFAIK there is no one in Australia who can do UK medicals. I recently renewed my Class1 in New Zealand.
My understanding is that it is now too expensive for Doctors who previously held the necessary approvals, to re qualify for an EASA approval, and keep current, when the number of renewals they might do is minimal.
That said I have heard of a Dr. In the Sydney area who may be prepared to jump through the necessary hoops, and so they may be available in the future. Watch this space!