Aliexpress
There’re some similar items on Aliexpress in my database. There may be some other items though.
| Image | Product (link) | Price | Coupons |
|---|---|---|---|
 |
Xiaomi MiHome Honeywell Gas Alarm | 50.68 USD | Paste “FUES03 or OUTDOOR3 or ODFW03” (may not work) |
 |
Xiaomi MiHome Honeywell Gas Alarm | 70.70 USD | Paste “ODF8 or OUTDOOR8” (may not work) |
More on Aliexpress… Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. There is one coupon available! Pretty cool, huh?
Link: Banggood product page
Coupon (55.36 USD): 6GSGIT
(CouponsFromChina.com tip: this code has to be applied in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Old coupons (from the oldest to the newest): 6OFFXM, affiliate6, aff7off, bgssaff9, BGaDmITAd, BGBFAFF2019, BGCITYADS2019, bGpAnDacHeCk, BGAQ20, BGSAMH, bGhOnEy10, BGSM15, BGSMOFF, bgshOOp10, BGSAMRTH, BGELIG0920, BgcLuBofErtA10, BG15SH12, BGSTHO15, BGHONEY2110, BGSHOM15, 13f142, BGSHE15
(these coupons are old, so probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi MiHome Honeywell Gas Alarm.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).