Rust along the front edge of a vinyl top is common on these. The thing that makes fixing these so hard is the tear down needed to do the job, not to mention replacing those pin head chrome windshield trim attachments.
The front half of the fastback roof is the same as a coupe, but at over $300 for the panel (NPD) you'd hafta really want it pretty bad. A good body guy can probably patch the existing roof. The labor would be about the same, but you'd save on buying the new panel. Getting a shop to do it at all will be difficult. Many shops will not do restoration work 'cuz there isn't enough money in it.
If you intend to put a new vinyl top on, it will at least save you a big paint bill since the whole car won't need to be painted to match the roof due to the faded old paint (but of course, you'd hafta' buy a new top and labor to install it). Frankly, I'd leave it off if the paint matches OK.
The fastback panel hasn't been around very long. I think it appeared for the first time in the 2008 catalog. We were asked to convert a coupe to a fastback using new parts back in 2006 and couldn't find a fastback roof anywhere. We had to modify the existing roof! Wait a while, and maybe a coupe panel will become available. Of course, as has already been suggested, you might still be able to find one in a back woods salvage yard some place. I know of one in Crestline Ohio that had a stripped out cut in half hulk that about the only good part left IS the front roof edge!.
To fix a rust hole in a roof you gotta' remove the vinyl top and trim, the headliner and pads, and repaint the roof when done. The vinyl top and most likely the headliner will be a total loss and will hafta be replaced. To get the headliner out means removal the front and rear glass. Often you will find hidden rust there too. The new headliners don't fit as good as the original ones did so be careful who does the work. Same with the vinyl top. I wish you luck and urge you to do the repair. We need to save these cars, but it ain't like doin' fenders!