Basically copy coupon, view price history or create e-mail price alert. Best price?
XM-L2, Cool White, 960LM, 23000cd, 300m, IPX-8 Waterproof
Aliexpress
I could not find it on Aliexpress. Click here to search by yourself.
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. One coupon is available. Cool!
Link: Banggood product page
1. ($15.29): linepayflt
this code has to be applied in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): HMT20
(probably won’t work, but you can try them out)
Price history and price alert
Price history (for all/most countries) for Revtronic MT20 Flashlight is here.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).