Aliexpress
Click here… to search for Original 2x Side Brushes for Xiaomi Vacuum on Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. As you can see I didn’t find any active coupon for this product right now…
Link: Banggood product page
Price: -3 USD
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Old coupons (from the oldest to the newest): vipupgrade8, PICODICOM, aff7off, bgssaff9, BGaDmITAd, bgchinafest, BGBFAFF2019, BGCITYADS2019, BG9NY, 2020CNY, BGVDay10%off, BGAFF7OFF, bGhOnEy10, BGHome15%, BGAFF10OFF, BG11SHOP, BG10OFFAFF, BGwhielabel, BG10OFFAFF1
(these coupons are old, so probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Original 2x Side Brushes for Xiaomi Vacuum.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).