The return of Ben McKay from a foot injury and Griffin Logue from suspension respectively has been tempered by Larkey's ongoing fitness battle with a hip pointer injury.
Larkey, who booted 12 goals in the opening three rounds, was severely restricted after suffering the injury in a collision with Jacob Weitering in the first quarter of North's Good Friday loss to Carlton and was kept goalless.
He trained away from North's main group on Thursday and appears touch-and-go to face the Lions at Mount Barker on Saturday.
"He just got one of those terrible hip pointers - I think anyone who's played the game has probably copped one at some point in time," coach Alastair Clarkson told reporters.
"It was such an innocuous clash with Weitering.
"But it looks like he's moving okay there so he's still got another couple of days.
"He might need to go to the line but we'll give him every chance."
McKay's first game of the season comes a week after twin brother Harry and his forward partner Charlie Curnow put North's undermanned backline to the sword.
He and Logue will be crucial to handling Brisbane talls Joe Daniher and Eric Hipwood.
"He's had that unfortunate foot injury and we've just been really patient," Clarkson said of McKay.
"For any player really but particularly a tall player, foot injuries are really risky because they're carrying so much weight through there.
"So we've been really cautious and he was chomping at the bit, wanted to get himself ready to play last week.
"It wasn't to be last week, but we're really keen for him to get back in and hopefully stabilise our defence."
Meanwhile Clarkson expected veteran midfielder Ben Cunnington to bounce back from being substituted against the Blues and deliver valuable grunt against Brisbane.
"He's a proud man and I'd be hoping that he'd want to respond," he said.
"He was well below his best last week and he understands that."
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