The West Indies are currently ninth. On September 30, the top eight will automatically win spots.
The winners of the cup in 1975 and 1979 and more recently champions of the world T20 events in 2012 and last year, are desperate to be there.
As it stands they will have competition, primarily, from Ireland, Zimbabwe, Afghanistan and Scotland for one of those last two spots.
The qualifying tournament next year is likely to be in either the United Arab Emirates, Zimbabwe or a joint operation by Ireland and Scotland.
The West Indies are heading to England shortly. After that, there is the trip to New Zealand.
If the authorities are to get a solid team together time is running short.
"We may only have eight ODIs against England and New Zealand in the next six months to prepare," Cricket West Indies chief executive Johnny Grave said.
"It is crucial that we can have our best-performing Windies players available for selection in these important games."
The West Indies board had insisted players had to be available for their domestic 50-over tournament to be eligible for selection.
Some of the best players weren't prepared to do that, preferring the lucrative global T20 circuit.
Lefthand batsman Darren Bravo's situation is different. He has been at loggerheads with controversial CWI boss Dave Cameron after Bravo called him "a big idiot" in a tweet over a contract dispute. Cameron didn't take it kindly.
Gayle's last ODI was against New Zealand at Wellington in the World Cup in 2015, when he slammed 61 in 33 balls, after Martin Guptill had smeared his stunning 237 not out, but he played a one-off T20 against India last week.
He believes "things have been steadily improving" between the board and players.
Never one to sell himself short, Gayle added that "the fans were happy to see me back on the field representating the West Indies. I definitely want to play the 2019 World Cup.
Other prominent players who may be beneficiaries of the desire to qualify for the World Cup in two years are former captain Darren Sammy, spectacular hitter Andre Russell and fiery batsman Marlon Samuels.