Aliexpress
Click here… to search for Xiaomi Portable Toilet Cleaning Brush on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. You can get coupon down below.
Link: Banggood product page
Coupon (12.77 USD): 13f142
(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): Hardware, e1b8e2, TTxBG10, 2019SPEDM, bgssaff9, BG3088, BG2756, AFfbG10, BGBFAFF2019, BGCITYADS2019, BG2020NS, BGVDay10%off, BGAFF10OFF, bGhOnEy10, BGdragonBoat, BGSS10%SW, bgshOOp10, BGHWDEALS, BgoFErTaSchInA10, BgcLuBofErtA10, BGCuponation10
(probably won’t work, but you can try them out)
Price history and price alert
Here is price history (for all/most countries) for Xiaomi Portable Toilet Cleaning Brush.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).