That was way to brief. The mining craze hit 290 cards pretty much by December. Stock was depleted and when it came back 290 was already going for more than the price cut 780's. Hell, it was getting almost to the point a 290 Ref was costing as much as a 780 Ti.
People seem to forget the Bitmining craze when they think back at the 290/290X prices. Because it was TERRIBLE. I keep linking this Anandtech article:
http://anandtech.com/show/7758/radeon-r9-290x-retail-prices-hit-900
This was in February 2014:
290X launched, I hated the ref cooler. Waited for custom cards, watched stock go zero. Then price hike, by April 2014 I got tired of waiting and snagged a Lightning 780 for $450. Meanwhile a 290 was still ~$500 at the time.
EDIT: At least for the time when 290/290X were fresh on the market and +6 months. Then the bubble burst and the value plummeted as people were unloading used cards. Then it was a golden time to buy 290X, going between $250-350 with rebates and games. I remember missing the $260 290X lightning (after rebates and selling vouchers) and kicking myself.