Hi Anne
With funds being a bit tight at the moment if I were you I'd ask the experts on the Pajero Owners Club
Click Here
These guys (and gals) may be able to give you good advice about where to have the repair done for less than £700, it's even been known for these friendly Paj owners to come round and do the job.
Whatever happens at least you will probably find out why you are having trouble with the cylider head so that you can make an informed decision.
I'm a Pajero owner myself, these trucks are usually bombproof. Is your Paj the 2.5 diesel, the 2.8 or the petrol V6?