I too have emailed the seller to ask for some more photos.
It's so easy to fake something like this. Print a script on some pre-faded paper. Use a number of different biros to copy autographs. Put a stain on the back...
One thing that does concern me is the line "FROM THE NOVEL BY GEORGE LUCAS".
This isn't something I've seen on any other Star Wars script. And as we all know, GL didn't write the novel. The novel was written my Donald F Glut and was based on the final shooting script. Perhaps the script did say this, but it just jumped out at me as wrong. Having said that there is another script claiming to be the fourth draft - here that also has the NOVEL line on it.
I could never justify paying $2000 unless I purchased it directly out of the hands of Gary Kurtz or another crew member.
I wil be keeping an eye on these, and perhaps contact the eventual winners. If there are any.