Aliexpress
Click here… to search for Xiaomi SOLOVE 360 Clip-on 2000mAh Fan on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. There is one coupon available! Pretty cool, huh?
Link: Banggood product page
Coupon (21.99 USD): 13f142
(CouponsFromChina.com tip: put item in your cart and apply coupon code there after clicking “Proceed to checkout”. Click to copy code and open shop)
Old coupons (from the oldest to the newest): HHHHHOT, vipupgrade8, Brand2, BGHU206, BGMIB2, BGHC20, 502C6B, BGSD52469, bGhOnEy10, BgcLuBofErtA10, BGCuponation10, BGAFF10OFF
(probably won’t work, but you can try them out)
Price history and price alert
Here is price history (for all/most countries) for Xiaomi SOLOVE 360 Clip-on 2000mAh Fan.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).