Aliexpress
Click here… to search for OnePlus 9R 5G 8/256GB Snap870 Global ROM on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in Hong Kong. I found coupon for you. Check this out.
Link: Banggood product page
Coupon (584.97 USD): Terence
(CouponsFromChina.com tip: this code has to be applied 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): BGOP9R56D, 13f142, BG9R2567, BGb81d84, BGD0C934, BGOP9R725, BG889172, BG25223e, BG348b74, BG0370ca, BG573e71, BG73fbb5, BG26255a, BG34b55b, BG43bdb2, BGa3adab, BG4026ec, BG3d74c8, BG88a37a, BGeffb9a, BGbe8a63, 2022ACTIESNL
(these coupons are old, so probably won’t work)
Price history and price alert
Here is price history (for all/most countries) for OnePlus 9R 5G 8/256GB Snap870 Global ROM.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).