Amazon with GLOCUSENT has the Glocusent 13 LEDs 120 Hrs Runtime Rechargeable Book Light (Black) for $9.99 - 50% off with coupon code Y8ZCD9OU at final checkout = $5.99 with free shipping on $35+ or with Prime. Has 94% positive Amazon reviews (more than 600 Amazon reviews in total). 

Amazon promo codes don’t always work on the first attempt. Try refreshing the page and re-entering the code.