It's really just timing. For a long time, the Sonokong was going for about 25 bucks sealed. It was exactly the same, going for a quarter of the price. I don't think you'll see that kind of pricing these days though.
Here's one for 60 bucks plus shipping:
https://www.ebay.com/itm/Transformer...YAAOSwDk5TvYgr
and an old thread about Sonokong:
http://www.cybertron.ca/boards/showt...t=18153&page=3
