Depends on what has failed. Was it the raising/lowering function or the drive?
If I remember correctly, it was a hydraulic drive (and brakes) at the front 2 wheels and a pair of hydraulic rams to a hinged upper platform.
The hydraulic power unit, I presume, was powered by a diesel.
Obviously the problem can't be as simple as burst hoses as that would take 15 minutes to replace a hose (30 mins to make one up).
Diesel Engine failed? (result, no power to drive hydraulic pumps).If it's something major like a sheared crank shaft, surely it wouldn't be difficult to change out the whole unit (with minor mods) for a similar powered unit.
Hyd. pump failure? Worn swash plates/ shattered swash plates? Casing failure on the pump? Scary and potentially lethal - power of hydraulics never ceases to amaze me. Steel will give before fluid will.
Hydraulic ram failure? Seals - no big deal. Bent ram? A little more serious. a lot more expensive. Sheared hinge pins - again, potentiallly lethal.
Hydraulic drive failure? Not familiar with Hydraulic drive systems but the beauty of the system is infinite variabilty of power without the need for a gearbox. Basically, think pump in reverse.
As ever, spares availabilty will probably be the major influence in the time it will take to repair.
Ofcourse, if it is a structural failure in the body of the hoist itself, that's a whole different can of worms.