if these cabs are original and in good condition it would be worth your time to get repaired,you need a good understanding of electronics and some basic tv knowledge to attempt this yourself.
if decide to go ahead and repair these monitors you will probably find all the information here on this forum,it is necessary to know the exact make and model number of the monitor to find the exact information.
please do not attempt this if you do not have some electronics experience,remember there are some very nasty voltages on monitors that can hurt you very badly.