What I have done in the past is call Customer Service to pay for a subscription for a friend, or gift something. You don't need their account information. The very helpful folks have been able to locate the account by the name of a character, server, and kin combination. Your gift can have your name on it or they can make it anonymous if you request. 
It's a nice thing you're doing for your friend.
I'd explain it to you, but I'm all out of Puppets and Crayons.
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GLADDEN: Moochy, 105 Minstrel R10 + alts CRICKHOLLOW: Moochy, 21 Minstrel