Just check coupons out (with price alert and history). Do you want to know what the best price is?
Working voltage: DC5-DC9V, Channels: up to 16 channel output, 2s Lipo recommended, Weight: 342g (without battery), Size: 158x 150x 58mm, 128* 64 resolution, Upgrade method: USB online upgrade, Display: 1.7-inch LCD display, Radio MCU: STM32F205VET6 (512kb), (factory with 4 * AA battery box, JR/FrSKY compatible module bay on rear side, Simulator mode: 3.5mm standard ppm output or USB HID, Firmware: JumperTX (an open source Firmware set based on the OpenTX Project), Voice support: YES, Gimbal Type: HALL Sensor, batteries not included)
Aliexpress
There’re some similar (or not) items 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. Well, there is one coupon available right now.
Link: Banggood product page
1. ($99.98): TTxBG10
apply code in your basket (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): 502C6B
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Check out price history chart (for all/most countries) for Jumper T12 Plus RC Transmitter JP4-in-1.
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)).