Basically copy coupon, view price history or create e-mail price alert. Best price?
Intel Celeron J3455, 15.6 inch FHD IPS Screen, 8GB DDR4 2400MHz RAM for Advanced Multitasking, 256GB SSD Storage Capacity, Intel HD500 Graphics
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 and price update (UTC):
Banggood
Banggood warehouse is located in China. I found coupon for you. Check this out.
Link: Banggood product page
1. ($339.49): Email5
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): BGTB9021, Wholesale20, aff7off, BGTB5237, BGTB55237, BGX8S5237, BGBFCR28, BGCITYADS2019, bGhOnEy10, BGAFF7OFF
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Price history (for all/most countries) for T-BAO TBOOK X8S 8/256GB J3455 Laptop 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)).