"a duo of" is correct and usable in written English.
It is used to describe two people or things that work together as a pair or team. Example: A duo of siblings walked on stage to perform their musical duet.
From Japan comes a duo of major genre heavyweights.
Lea Bertucci and Leila Bordreuil are a duo of electroacoustic Bass Clarinet and Cello.
Cooking Sections (Daniel Fernández Pascual & Alon Schwabe) is a duo of spatial practitioners based in London.
Eventually the group became a duo of Ms. Keenan and Mr. Cargill.
The night began with Filament, a duo of Sachiko M. and Otomo Yoshihide, both from Japan.
A duo of baked clams and garlicky shrimp, while hardly subtle, nonetheless worked as well.
Phlegm responded by adding a duo of Edward Gorey-esque characters beneath the wave.
Sharing Saturday's concert were Duane Pitre and Eleh, a duo of drone-oriented performers billed jointly as Pitreleh.
Why end Day 1 with a duo of Al Di Meola and Gonzalo Rubalcaba playing glossy guitar-and-piano rhapsodies?
Read more here The ever-popular documentary-maker returns to the UK with a duo of harrowing investigations.
Peaches Geldof is half of a duo of TV presenters filming links for the broadcast before the gig.
