UPDATE: Having been unable to find a salvage hatch, I brought the specialists back to give it a try. In one hour they had the hatch off, dismantled, stripped, cleaned, reglued, reassembled and reinstalled. They said to wait 48 hours before exposing it to weather, etc., and not to reattach the struts for about a week. Apparently the struts place a lot of pressure on the hatch frame.
The good news is that it is repaired, at least for now, and it only cost $100. The bad news is that there is absolutely no guarantee that it stay fixed.
More good news is that, barring unforseen disaster, I'll be able to attend the Gathering in Hershey.