Higashiyama Line N1000 Why So Rare?

[Super]

I always thought that the Tomy trains with headlights were relatively newer releases so why is this Higashiyama Line N1000 so expensive? Apparently it was released in 2008 for $20 or less.

http://japamart.com/auctoolitem.php?url=.../188827024

http://www.amazon.com/gp/offer-listing/B...irect=true

http://www.1999.co.jp/eng/10064912