Thanks everyone! At the moment the fees for Citibank would be about $60 a month, in order to make a $300 a month loan payment. Yikes! But if I set up another Paypal account with a US account I could transfer money with a 5% fee (around that) and it would still only be $15! So if I could find a bank account with no monthly fee if I hold a zero balance that would be ideal.

I'm going to look at Pentagon Federal, thanks! My brother is an ex-marine so it seems I might qualify anyway. He also has an account with another government credit union so I'm also going to see if maybe I can join that one directly. I can even go in person next time I visit "home". But now I have a heads-up on the social security number issue so can start looking into that. (Ironically my social security number is my student loan account number.)

The other option I'm considering is a huge one-off payment for the year if I could wangle it somehow. That would limit my fees at least.