Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. There is one coupon right now! Check this out.
Link: Banggood product page
Coupon (114.83 USD): BG10OFFAFF1
(CouponsFromChina.com tip: paste coupon code in your cart and click Apply 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): BgAuMotor, AM15prime, AMPrime01, Automo, Automo1, BGAutos, bGhOnEy10, BGCARELEC, BGINMO, 7bcdf9, BGAFF10OFF, BGCuponation10, BGHONEY2110, BG10OFFAFF, BGwhielabel
(these coupons are old, so probably won’t work)
Price history and price alert
Here is price history (for all/most countries) for Xiaomi Amazfit Rainproof Windproof Motorcycle Jacket.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).