Chasing a misfire.

For a while now I have been running down why cylinder 8 is misfiring. I checked all ignition components, they are all fine. I did a compression check on the cylinder, and it was very low. If i loosen both rockers on that cylinder, compression comes right up. I am not an expert on this, but it seems that the valves are stuck open by the rockers. Is this an easy fix, Should I send the heads out to be repaired, or just buy new ones? This is a stock 2000 360 magnum for now, but eventually it will be getting a bigger cam. let me know what you guys would do.