Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. I found coupon for you. Check this out.
Link: Banggood product page
Coupon (488.74 USD): BGAlerabatKL
(CouponsFromChina.com tip: apply code in your basket (cart) after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Price history and price alert
Here is price history (for all/most countries) for Xiaomi 430W Bluetooth 5.0 SoundBar with Subwoofer.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).