Eaton, who turns 30 on March 29, has played two seasons for the Hurricanes (2011-12) and joined the Western Force wider trainings squad last season in Super Rugby.
The Hastings-born player got on the field for the Canes 28 times and scored 15 points, including three tries.
Eaton has 76 caps for the Magpies, scoring 30 points, after making his debut in 2007.
The former St John's College pupil has yet to make an appearance for the Perth-based franchise after the Force called him in last year as cover for Wallaby halfback Brett Sheehan.
Hastings-born Mathewson, who is in the final leg of his two-season contract with the Force, and Mick Snowden were the first-choice options for the Force last Super Rugby season.
The former Hastings Boys' High School pupil and Victoria University graduate started off the ITM Cup season with the Magpies last winter but Eaton gave him a run for his money a few rounds into the national provincial competition.
Eaton shoved his boot into the door of the Wellington franchise team in 2011 when Piri Weepu got injured, although the former All Black halfback returned late in the campaign. He ran on the field for 11 appearances, including eight in the starting berth.
In his second full season in 2012, Eaton predominantly warmed the bench, with the Canes' stable preferring TJ Perenara, although he assumed the latter's mantle of halfback towards the end of the season when Perenara got injured.
He became a regular in the Magpies equation in 2009, when former Hurricanes, Highlanders and All Black halfback Danny Lee, of Hastings, retired a year before.
In Easter last year, Eaton's wife, Hannah, tragically died in a car crash.
The mother, part-time model and midwifery graduate was travelling along State Highway 26 near Puriri, between Paeroa and Thames, when her vehicle was in a collision with another.
Eaton got the news while preparing for his debut off the bench for the Western Force against the Waratahs in Sydney. He withdrew from the game to join their now 5-year-old daughter, Layla.
Philpott said he had met Eaton, who was in great shape.
"He's a fabulous dad and is doing all right."
He said the Magpies, who won the Ranfurly Shield last year and lost in the second-tier Championship final to Tasman Makos to miss out on promotion to the Premiership, had 10 different clubs to pick halfbacks from as back-ups this winter.
Among the home-grown talent front runners are former under-20 World Cup rep Sheridan Rangihuna (Napier Technical Old Boys) and Adam Ross (Hastings Rugby and Sport).
Philpott and co-coach Lee also have inherited the services of newcomer Ellery Wilson.
The 23-year-old is a former St Pat's College pupil from Wellington who had drifted to rugby league in Australia in 2008, signing a two-year contract with the Wests Tigers.
"He was scouted by Aaron Mauger to join the Canterbury rugby academy," said Philpott who also trained Wilson as a Canterbury Colts player. "He has completed a uni degree so he's been brought into club footy in a bid to make the Magpies."
The 32 Magpies squad members, who have been working out on individual agendas, will assemble on January 27 for formal training camps starting next month.
