Just check coupons out (with price alert and history). You probably want to know what is the best price?
Channels: up to 16 channels, Battery capacity: 2000mAh, Operating current: 270mah maximum, Operating voltage: 6-15V(2S 3S lipo are acceptable)
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. Too bad there’s no coupon right now in Banggood.
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): 10frse, e2bcea, x9dplusse, 502C6B, TTxBG10, FRX9DSE, 10Frsky, aff7off, bGhOnEy10, 7bcdf9, BGRRCB10
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Other warehouses/versions
This item is available in 3 another warehouse/versions!
1. China – FrSky Taranis X9D Plus SE 16CH Transmitter Rock Monster ($-3)
2. China – FrSky Taranis X9D Plus SE 16CH Transmitter Blazing Skull ($-3)
3. China – FrSky Taranis X9D Plus SE 16CH Transmitter Camouflage ($-3)
Price history and price alert
Price history (for all/most countries) for FrSky Taranis X9D Plus SE 16CH Transmitter Carbon Fiber is here.
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)).