Basically copy coupon, view price history or create e-mail price alert. Best price?
ROM 256GB UFS 3.0 2-LANE, GPU Adreno 640, up to 2.84 GHz), OS OxygenOS based on Android 9, 7nm, RAM 8GB LPDDR4X, 4000mAh (non-removable), Protection 3D Corning Gorilla Glass 6, with Qualcomm AI Engine, Display Size 6.67 Inch 2K+ HDR10+, Type Fluid AMOLED, Resolution 1440x 3120 pixels QHD+, CPU Qualcomm Snapdragon 855 (Octa-core
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 Hong Kong.
Link: Banggood product page
1. ($599.99): BG7P401
2. ($812.99): Email5
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 and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGOP7PRO8G, BGOP7PRO1, affiliate6, BGOP7PROB, BG7PROERU, BGOP7PRO, BGOP7PRO629, aff7off, BGOP7P73, BGletni17pro, BGOP7P79, bgssaff9, BGONEP7P, BGOP7P, bgop7pa8, BGOP7PUIJ, od7off, BGOP7pro654, BGOP7P298, bguijop7p, bg92op7p, BGaDmITAd, BGOP7P899, BG99OP7, BG99PRO7, BGOP7PGR8, BGTYOP7P8, 7bcdf9, BGOP7PGRU8, BGOP7PGRTU8, BGOP7C8, BGD11OP7P, BGBFAFF2019, BG11OP7P8, BG3COP7P8256, BGCITYADS2019, BGBFOP7P8, BGBF7T8256
(these coupons are old, so probably won’t work)
Price history and price alert
Price history (for all/most countries) for OnePlus 7 Pro 8/256GB Global ROM Gold is here.
Price records source(s): Gearbest, 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)).