Aliexpress
Click here… to search for Xiaomi 1MORE E1003 Piston 2 Earphones on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. I found coupon for you. Check this out.
Link: Banggood product page
Coupon (20.84 USD): AFfbG10
(CouponsFromChina.com tip: just apply this code in your 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): d4de0b, 502C6B, TTxBG10, BG3CSUM, BG20QCY
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Price history (for all/most countries) for Xiaomi 1MORE E1003 Piston 2 Earphones is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).