Hello Ben,
I used to ride a 94KX250 a few years back and do not recall damping rods being a "common" problem on those models. I know however that those rods usually get damaged when not serviced properly:
- loose lock-nut under the fork cap... Than the thread dies real quick!
- pliers are used to hold the rod when removing the base valve!
I believe those parts are available through Kawasaki and problably through companies like Race-Tech too (not sure though).
... if tuned well, that KX is a really good bike.
Take care,
Yoken.