See also what Arcticfox designer/developer Damon Slye has to say about what they used to make their game:
http://www.greatgamesexperiment.com/user/Damon%20Slye"Dynamix' first huge contract with EA for a whopping total budget of $35K ! We had finally hit the big-time! (or so we thought) We released this, EA's first original title for the Amiga, in 1986. We developed on a pre-release Amiga packaged in a black steel box with a wooden keyboard."
The seller needs to post more details or better photos.
If someone asks one of the original amiga team members they surely would be able to tell if it is the Lorraine prototype or not. I would have thought one of them would keep it themselves.