* Union leaders struggle to sell draft wage deal to workers
* Government offer of 7.5 percent hike said to be final
* South Africa expects worst year for strikes since 1995
(Recasts with union chiefs agreeing deal, adds background)
By Peroshni Govender
JOHANNESBURG, Sept 7 (Reuters) - Leaders of South Africa's labour federation COSATU have agreed with the government on a 7.5 percent wage rise but have so far failed to sell the draft deal to rank-and-file workers, union officials said on Tuesday.
They told Reuters that COSATU leaders had approved the rise last week and understood there was no way to attain the 8.6 percent the workers demanded during a strike of nearly three weeks that was suspended on Monday for more talks.
But union leaders were struggling to win over workers who stand to lose most of a month's salary due to the walkout and had already rejected the 7.5 percent offer last week.
"Unions were shocked by the manner of the rejections, the mandate was unambiguous, it was a no," said the COSATU official.
While union leaders might understand the government is in no position to increase its offer, workers have disagreed.
"Our leaders are sellouts, we don't want to accept the agreement," said a teacher from Mpumalanga province who did not want to be named.
The government has said it will not pay strikers for days not worked and rejects any suggestion it could renegotiate.
The offered rise is already more than double the inflation rate and the government argues it cannot find more money despite what looks set to be the worst year for strikes since 1995 in Africa's biggest economy -- in terms of work days lost.
"The draft document on the table is a COSATU draft document. The proposal was a compromise document that was compiled by COSATU," said a COSATU source who declined to be named.
"They took it to the employer (government) and said: 'Here is what we propose, 8 percent and 800 rand'. The employer said: 'The proposal is fine but I can't give you 8 percent, I can give you 7.5 percent'," he said.
SUBSIDY
Unions representing 1.3 million workers suspended their strike to allow for further talks on the government's wage offer plus a housing subsidy of 800 rand ($110) a month, less than the 1,000 rand a month they demand.
But while the unions have said in public that negotiations with the government will continue for 21 days, union officials said 19 unions affiliated to COSATU and the separate Independent Labour Congress had accepted the draft proposal.
"The 21 days is for unions to consult their members and explain the offer. We want to resolve this matter as soon as possible and hope to hear from the unions before the 21 days," said government's negotiator Themba Maseko."
One union official said the draft proposal to end the strike had been presented to the government by COSATU Secretary General Zwelinzima Vavi. He quoted Vavi as saying, "This is the best deal we can get."
Relations between labour and the government are complicated in a country where COSATU both represents workers and makes up part of the ruling alliance led by President Jacob Zuma's African National Congress.
Economists believe the labour action has so far cost the economy about 1 billion rand a day and a prolonged strike could harm growth prospects for an economy already lagging other emerging markets.
Any agreement to end the dispute is likely to swell state spending by at least 1 to 2 percent, forcing the government to find new funds just as it tries to bring down a deficit totalling 6.7 percent of gross domestic product.
The public sector strike cost an estimated 12 million man days, bringing the total days lost to strikes this year to 13.25 million -- more than four times the number in 2009, said analyst Jackie Kelly at labour consultancy Andrew Levy and Associates. (Additional reporting by Marius Bosch; Editing by Mark Heinrich)