Aliexpress
There’re some similar items on Aliexpress in my database. There may be some other items though.
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (53.04 USD): BGSMOFF
Coupon (57.40 USD): 7d18f7
(CouponsFromChina.com tip: you should apply the coupon 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): Mumlatzim17, 6OFFXM, 16e906, affiliate6, BGss506, bgssaff9, aff7off, BGaDmITAd, BGBFAFF2019, BGCITYADS2019, 2020CNY, BGAQ20, BGSAMH, bGhOnEy10, BGSM15
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Here is price history (for all/most countries) for Xiaomi Mijia Smart Home Aqara Security Kit.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).