The ACT Brumbies skipper, who also captained his country last year, limped off the pitch with a calf injury early on in a loss to the Waikato Chiefs last weekend.
Alaalatoa will miss Friday's match against the Melbourne Rebels in the final round of the regular season and said the July 8 test against South Africa in Pretoria was a realistic prospect.
"For sure, but for me mostly the target is a couple of weeks," he told reporters in Canberra on Thursday.
"Soft-tissue injuries are all dependent...on the individual and how they heal, and I'm already ahead of where I'm meant to be."
Australia can ill-afford to lose an experienced tighthead prop in a World Cup year and Alaalatoa's words will be music to the ears of coach Eddie Jones.
The Brumbies are already assured of a place in the Super Rugby playoff quarter-finals but need to beat the Rebels in Canberra to be sure of home advantage in the first knockout round.
