Sounds similar to Comet and Diamond. I've had a comet GP6 in service since 1994. It's my guess that you're out of luck. For what these things cost and for the trouble you'd go through sourcing and shipping parts if they were even available, it's repair by replacement. If it's something simple like a cracked radome or other mechanical problem you've got nothing to lose by patching it together with whatever means you decide are worth it.
Mark K5LXP
Albuquerque, NM