Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (113.99 USD): bGhOnEy10
Coupon (116.53 USD): Parts8
(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)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): T8SGPL, T8SG105, 502C6B, 99T8SG, TTxBG10, BGss11, BGPAYPALSS, BGJT8SG2, BGaDmITAd
(there’s a little possibility that old coupon will work)
Price history and price alert
Check out price history chart (for all/most countries) for Jumper T8SG V2.0 Plus RC Transmitter.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).