Fixed costs are high, meaning the factories are operating at a loss even after revenues from producing the lifejackets are taken into account, he said.
Mr Brown raised the plight of the factories in a debate in the House of Commons on Tuesday.
Now he and fellow Fife MPs Thomas Docherty and Lindsay Roy want to set up a tripartite meeting, involving the governments and Fife Council.
The factories' losses, which they say have fallen to £80,000 this year from £1.6 million two years ago, could be wiped out if transitional support is provided, the three Labour MPs argue.
Mr Brown said: "We need the three parties who can help fund a rescue to come together to pool their commitments and resources so that the UK Government raises its current offer of £6,400 per disabled employee over three years and the Scottish Government raises its 18-month maximum of £5,000 per disabled worker. Even taken together, these offers are not enough to wipe out the annual deficits overnight. The Fife factories can be viable in a short period but they need more time."