Many accurate 1921 census transcriptions have already been added to the pub history site, including London, and parts of Middlesex. If you can contribute to the site, send me some details to Kevan, along with some description of the specific property.
Highgate pub history index
A listing of historical public houses, Taverns, Inns, Beer Houses and Hotels in Middlesex.
Residents at this address
See Archway Tavern