Rew, who Jones coached pre-Olympics, and Barber live in Melbourne.
While it is a teams' champs, the Kiwis are competing as individuals.
Former Taradale High School pupil Langley, who is in a gap year from tertiary studies, has been working at the Countdown supermarket in Napier to save money for her trip.
The talented teen had actually broken her qualifying standard time in her distance with a national record time of 51m 54s at the New Zealand Championship meeting in Dunedin early last month.
"I've also beaten that time twice since so I got my personal best and I'm quite happy with that," she says, after breaking the national secondary schools' record for the 2000m race at Aorangi Park track last December.
The Napier Harriers Club member sees the time of the 2014 winner Duan Dandan as a good yardstick.
Dandan, of China, clocked 43:05 in Taicang in the previous team world champs.
"In Rome I want to break the 50-minute mark, around 49:50, because 49:29 is the New Zealand record."
While she has missed this year's IAAF World Junior Championship cull because of her birth date, she still wants to see if she can make that qualifying time in Rome.
"I probably won't go if I qualify for that time because the cut-off is unfortunately in April."
She reconciles that fleeting disappointment with better bang for her dollar.
"I'd rather go to Australia a few times than for just one race in Poland."
Most of her supermarket earnings will take care of her everyday costs, such as daily transport and food, in Rome.
"I've been saving a lot of money for this."
She is indebted to Race Walking NZ, Athletics NZ, Napier Harriers, Napier Athletics Club, Sport Hawke's Bay, Tremains and HB-Gisborne Athletics Centre for their sponsorship.
Bledisloe Primary School also held a mufti day last Thursday for the "old girl".
"When I return [from Rome] I'll talk to the school about it."
When she started out raising funds, she anticipated a torrid and stressful time but the generosity of people and organisations blew her away.
"It's amazing to know so many people support me and want me to do well. It makes me even more determined to do well in Rome."
In the excitement she momentarily forgets her parents, Diane and Craig, but recovers to acknowledge their never-ending support.
"They've told me that whatever balance is left for me to make my target, they'll pay for it."
An avid runner from the age of 13 in 5km to 10km distances - after coach Mick Cull spotted her talent - Langley started questioning her motives in the discipline a few years later as she hit a plateau.
Any doubts she harboured about the peculiarities of race walking were nipped in the bud when Jones started mentoring her to head-turning times.
"No one can go under the one-hour mark in New Zealand in my age group.
"In Hawke's Bay, there's no one except for me and Graeme," says Langley, who in February competed in an Adelaide meeting where the top three finished below 48 minutes.
"That's pretty amazing," she says, after finishing fifth at the Oceania championship to make the Rome qualifying time.