Hello,
I'm a moderator, but I don't know how to give information of country to non SRC users (example: https://www.speedrun.com/sm64#0_Star ). Anyone knows that?
Thank you.

use brackets for that "[" "]"  
e.g. "[jp]" for the japanese flag.
note that this will prevent any account from claiming the run on run creation, even if the name matches.
Putting in just "HowDenKing" would link it with my account, putting in "[eu]HowDenKing" does not.

/edit:

If you need any other country codes, 
you can go to https://www.speedrun.com/users and select a country.
then check your URL for "#xx" for the 2 characters you need.

Country of Non SRC Users?