Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. One coupon is available. Cool!
Link: Banggood product page
Coupon (38.24 USD): BGAudio3
(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)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGaa00fd, BGAUDIO, BGd8beec, BG1b5830
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Do you need price history chart (for all/most countries) for E50 Bluetooth V5.0 Earphones Sunglasses? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).