If you search for a proof of single status certificate to use abroad, our website: usapostille.com provides it.
We provide attestation service for no record of a marriage certificate issued by the US Bureau of Vital Statics (Health Departments), which is used in countries participating in the Hague Convention, because we receive an apostille certificate of No Record of a Marriage from the secretary of the state office of the state, where the document was issued. And we help persons authenticate the proof certificate from the US Department of State and the embassy of the destination country in Washington DC.
If your documents will be used in countries not participating in The Hague, legalization of the embassy is necessary to recognize them. You can order it from our site too.