This is what the embassy's website says (I assume you're talking about the I-130 application)
Filing Fee: The fee for filing an I-130 or an I-360 is $185. The fee is payable by U.S. dollar cashier's check, U.S. Dollar money order, or International bank draft made out to the U.S. Disbursing Officer, or by Credit Card, Visa, MasterCard, Diners Club, Discover or American Express. Do not mail cash or personal checks. Please print your name and complete address on the back of the remittance. If payment by credit card you may download the form from this website and attached the completed form to the petition (on top).
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BUT - I don't know where to get a US$ cashier's check or a US$ money order, or International bank draft....