The Sydney Roosters playmaker hit top form against the Dolphins in the preliminary final after his miracle return from an ankle injury to guide the Tricolours to the grand final against Newcastle, and is 80 minutes away from being selected in the World Cup team.
Walters said he looked at "three criteria" around representative selection, and Walker has ticked the two he has control over.
"Previous history in the jersey, Origin form and what happens in the finals series are equally important," Walters told AAP.
"None carries more weight than the other, but it is about flexibility with the side and knowing your players.
"Sam's name will be brought up in the selection meetings for sure. We thought he was eliminated, but with his re-emergence he has put himself back in the picture.
"Sam has only had a few big games in his career so far and all of them he has handled well. That's always a good sign.
"He can come up with the right play, and his kicking game is so good."
Walker had a superb State of Origin debut and was man of the match in game two of the 2-1 series loss to NSW, apart from guiding the Roosters to the decider with distinction.
The cruel season-ending injury to Penrith half Nathan Cleary has opened the door for Walker and Parramatta and NSW playmaker Mitchell Moses to state their case.
"Mitch has been there before in 2024 and played well at halfback when Nathan was out," Walters said.
"He's got good form in the Australia jersey. Last year I thought he was very good on the Ashes tour.
"He didn't manage to get a game in, but he was very good around the group."
North Queensland co-captain Tom Dearden is also a candidate after shining for the Maroons in last year's series win and playing six Tests at five-eighth and off the bench in the previous two years.
Former Test half Greg Alexander said Walker was "comfortably a better player this year than he was last year".
"There is a bit of competition with Mitch Moses, but Sam has played the footy this year that shows he is ready to play for Australia," Alexander told AAP.
It is in defence that Alexander has been blown away.
"Sam is a smaller player, but his defence has been very good," he said.
"I don't think Billy Slater would have played Sam (in Origin) if he didn't think his defence could handle it. That's one area that I think Sam has excelled this year.Â
"There is no weakness, and I have done Roosters games this year (for Fox League) where I have said on multiple occasions 'that is a great tackle from Sam Walker'."
Alexander said Walker had always had the ability to come up with a play, but this year he had been more multi-dimensional.
"This year he is a better ball player," he said.
"He has got great vision with passing and kicking, but I think his ball-playing has improved where he can go to the line with confidence and get the play right, whether he runs or passes to put someone in space."