Thanks for the info!
When it broke down while riding, it was a relatively internal click/crack sound and the motor died. Didn't feel like any major internal damage. I could be wrong. But, hoping its a small thing.
The previous owner had taken the XR200R to a Honda dealership and they bored it out to the next size up piston and rebuilt the entire top end...from what they told me. I assume they went the next size up in piston and that I'll be able to replace the parts with readily available size parts, if needed.