I looked at that auction. The seler does state in the revision of his listing that he doesn't know for sure if it is a reissue or original, and there is no reason to suspect him of actualy beng an expert or for trying to mislead (otherwise he'd keep quiet about it).
That auction has nearly three more days to go so it may be more than $900 in the end. But an original in NM condition would fetch $3500 to $4000 in frantic last minute bidding (I know, I've wached plenty of these go for those prices).
In fact, if you search e-pay for recently completed auctions for this unit you will see that one went on 08 April for $3,995, another one went for $4,100 on 14 April and a third sold for $4,100 (13 bids) on 20 April.
I should have bought one two years ago because I think these units doubled in price in that time.