Have a go with merchantplus.com. They're in the process of getting me one (I am pretty sure it's with Chase Bank); I am in the same position as you (non-US citizen with a US company) and I have already been pre-approved.
We're likely to end up with a worse rate then US citizens would, but it's still better then no merchant account.
We're likely to end up with a worse rate then US citizens would, but it's still better then no merchant account.