The official has changed the recharge rules to only Malaysia,Singapore,HK and the NA server, but NA SERVER we just can do part. We can try in other region before you pay message us your username and server id we will check if we can do it.
For other region players:
1. Use VPN to start up a new riot account in these regions(preferably Malaysia).
2. Login to LOL without using VPN, so your new account will be in the same server as your main account.
3. Then you can gift yourself skins using the new account.