SYDNEY (REUTERS) - A number stamped on a piece of aircraft debris found on La Reunion Island could help quickly identify whether it came Malaysia Airlines Flight MH370, missing for more than 500 days, Australia's deputy prime minister said on Thursday.

Officials believe it is "almost certain" that the debris, thought to be a wing part called a flaperon, belongs to a Boeing 777 aircraft but have yet to confirm it is from MH370.

The number was not a serial number but could have been some sort of maintenance number that would help with trying to identify it, Warren Truss told reporters.

"This kind of work is obviously going to take some time although the number may help to identify the aircraft parts, assuming that's what they are, much more quickly than might otherwise be the case," he said.

MH370 which disappeared in March last year carrying 239 passengers and crew from the Malaysian capital, Kuala Lumpur, to Beijing, in what has become one of the greatest mysteries in aviation history.

Ocean experts say currents could have carried debris the thousands of kilometres from the estimated crash site to Reunion, off the coast of Madagascar, over the intervening 16 months.