The Parramatta pair were directly involved in each of Australia’s 22 points; Lomax clinched a double and kicked three goals, while Moses scored a try and assisted another.
Incoming recruit Lomax was among Australia’s top performers, leading the way with a team-high 200 run metres in addition to his 14-point haul.
The exciting outside back showed great strength and awareness for his two tries, and landed three important goals for the Kangaroos.
Moses, meanwhile, enjoyed his strongest performance in Green & Gold after a relatively quiet debut the previous week.
The Eels halfback played a terrific inside pass for Australia’s opener, and then ran away for the match-sealing try in the closing stages.
The victory sends Australia to the Final of the Pacific Cup, where they will face the winner of this week’s clash between New Zealand and Tonga.
The Finals of the Pacific Championships will be played on Sunday 10 November at Parramatta’s own CommBank Stadium.