Was told by my avionics shop here in the US that some spares for the KI-214s are no longer available, so depending on what the problem is, it may not be (economicaly) repairable. We traded our old KX-170 and 214 in on a newer KY97 and Collins CDI. You might try shopping eBay for a used unit if you don't want to change radios.
Alternately, Eastern Avionics in Florida still lists reconditioned units for $1095
http://www.avionix.com/indicator.html