Depends. There's nothing special about the Amiga itself; there are many 2500s out there.

I DO think however, that the contents of the hard-drive need archiving and given over to archive.org - providing NASA are OK with that of course.

What scares me a little bit is that the seller has clearly performed some 'write' operations on the data - you can see him running LHA to extract an archive. If he's done that then there is no telling what else he's done and what may have been lost or contaminated in the process. :(

Looking at the price he's clearly just trying to cash in, and has no interest in it's real historic value.