Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in Hong Kong. There are no active coupons for this product, but the price is pretty low isn’t it?
Link: Banggood product page
Price: -3 USD
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGOP9R256D, 13f142, BG9R1227, BG048b16, BG5061b3, BGOP9R256725, BG20eae8, BG392bb0, BG582304, BG3d69cb, BG72b51b, BG37d264, BGd55031, BGbb264b, BG187746, BG5b4cdf, BG5a4f62, BGefdc99, BG56ad07, BGc99d64
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Do you need price history chart (for all/most countries) for OnePlus 9R 5G 12/256GB Global ROM? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).