Aussie members -Melbourne to Heathrow

[AJSP]

I’m after some advice / help. I want to get a flight for my sis.
 

My sister lives in Aus and I want to get her over to see my parents in March / April 2026. She’s a big lass so as it’s a long flight Business Class is the preferred option although PE may also be ok. 
 

I’ve had a look online for flights but I’d welcome ideas / recommendations for a flight with one stop and circa 6/8k AUD with not huge flight times. 

Thanks in advance