Don't use deed (even if it's for the UK), use "instrument" instead.
Presumably it's a "notarial instrument".

To quote (at length) our estimable colleague Rebecca Jowers, speaking on a related question:

In English a deed is "a written instrument by which land is conveyed" or "at common law, any written instrument that is signed, sealed, and delivered and that conveys some interest in property." (Blacks Law Dictionary, 7th ed.) But since "escrituras" are notarial documents that often certify many other types of transactions, "deed" as a translation of “escritura” is not an accurate term. Moreover, even when the “escritura” in question concerns the transfer of real property, the term "deed" in English does not in any way convey the idea of a document that has been certified by a (civil law) notary and the role that such instruments play in civil law systems, i.e., the fact that a transaction recorded by a civil law notary will henceforth become a part of his notarial records (“protocolo”), will serve as official evidence of that transaction vis-à-vis third parties, and may be submitted “as is” as evidence of such in court. A “deed” in Anglo-American legal systems has none of these features.
https://www.proz.com/kudoz/spanish-to-english/law-contracts/...