worn out bearing noise in getrag box

[a-drain]

hi guys
my gearbox for a while now has had a whirring sort of sound like a worn out bearing n has gotten worse. It only seems to happen in neutral first second n third and the noise disapears when the cutch s pushed in (so it is between the clutch and the box). Dose any one know if this can be fixed easily by replacing one or two bearings or isit a fuller rebuild of the box. trying to do it cheap as dont have alot of money. have tried heavier oil in the box

[GTP 85]

Its a getrag... every one i have driven is noisey in the first few gears. Still drive perfectly fine though