Brown Switch), Red Switch, ESC/FN Key is GKLC Dual Light Switch, Model GK66, Keycaps ABS, Key Number 66 Key, 380mA, Backlit RGB, Switch Gateron Optical Switch (Blue Switch, Brand Skyloong (Geek), Dimension 295*105*45mm, Connection USB Type-C Wired (Detachable), Power 5V, Cable Length 1.6M.
Basically copy coupon, view price history or create e-mail price alert. You probably want to know what is the best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
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. I don’t think there is an active coupon right now – at least in my database.
Link: Banggood product page
Price: $-3
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!
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): BGCPP018, AFfbG10, BGCITYADS2019, BGVDay10%off, bGhOnEy10, BGdragonBoat
(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 GK66 USB-C Split-Spacebar Gateron Switch Keyboard. The lowest price was: $39.69.
Price records source(s): 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)).