Not to argue as kitty is far more an expert on consoles and retro stuff in general then me but I took a quick look on ebay and the last one to sell, which imo determines the real price was here:
http://www.ebay.com/itm/SHARP-19-TEL...p2047675.l2557
It sold for 400 USD with 70 USD shipping and only shipped in the US.
If you were willing to do a worldwide auction on that thing, who knows?
Of course, shipping would be a nightmare