Aside from the US embassy or consulate, there is no such thing as a "US notary", as all notaries are appointed by the individual US states. US state-appointed public notaries are generally not authorised under state law to notarise documents outside their state borders nevermind the US border. The commission of a notary public is limited to the jurisdiction within the particular state in the U.S. for which the commission was issued. It is only the state of Florida which authorises (further to Florida Statute 118) the right for Florida Civil Law Notaries (not public notaries) to notarise documents outside of the US border. Most US states do acknowledge the use of foreign notaries and the Hague convention. Generally you must look to the state's legislation to determine what notaries outside the USA are acceptable.