Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (15.99 USD): BG0f268c
Coupon (19.22 USD): tRaDetRaCKeR
Coupon (19.22 USD): pROMo8cuPoN
(CouponsFromChina.com tip: just apply this code in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGPL528, BG92aad3, BGa04209, BG443b85
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Do you need price history chart (for all/most countries) for NUSITE 11.5 Inch LCD Writing Tablet Colorful? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).