International eligibility remains unsettled four weeks before the World Cup, with several players listed in more than one preliminary 40-man squad.
AAP understands Mitch Moses would select Australia if included in the final 23, to be announced after the NRL grand final.
The Parramatta halfback played for Lebanon at the 2017 and 2022 World Cups, where he would secure their No.7 jersey, but Kevin Walters previously selected him for last year's Ashes tour.
Australia's playmaking options also include Nathan Cleary, Tom Dearden, Cameron Munster, Ethan Strange, Sam Walker and Matt Burton.
Cleary's availability is uncertain after a bone-stress injury in his right foot, although Penrith believe he could play their preliminary final against either the Warriors or Newcastle.
Tino Fa'asuamaleaui is also expected to favour Australia over Samoa, while Samoa have lost Payne Haas to off-season surgery and Adam Doueihi to shoulder surgery.
Francis Manuleleua and Tom Mikaele are expected to represent Samoa despite appearing in New Zealand's squad. Jacob Laban and Tanner Stowers-Smith are likely to choose New Zealand.
Robert Toia and Siua Wong have committed to Tonga, while Fonua Pole, Dallin Watene-Zelezniak and Salesi Foketi remain eligible for Tonga or New Zealand.
Josh Papalii's international future is unclear after his NRL retirement. Charnze Nicoll-Klokstad, Xavier Willison and Oregon Kaufusi also have multiple options.
Fiji is still checking the eligibility of Wests Tigers brothers Samuela, Latu and Sione Fainu, who prefer Fiji but can represent Tonga.