Aliexpress
Click here… to search for GameSir T6 Bluetooth Stretch Game Controller on Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. There is one coupon available! Pretty cool, huh?
Link: Banggood product page
Coupon (21.91 USD): BG717000
(CouponsFromChina.com tip: coupon code has to be applied in shop’s cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Old coupons (from the oldest to the newest): BGd0b05d, BG2589f4, 00c906, 8BGwbg2204, 2203ActiesNL, tRaDetRaCKeR, 8wEbgaInS5, BGVGAMES, BG8ReviTrage, Cuponation9, BGVDGA07
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Do you need price history chart (for all/most countries) for GameSir T6 Bluetooth Stretch Game Controller? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).