In case anyone is interested, I uploaded my Rootes document to a file-sharing site, so it's available for all to see. The data comes from
Rootes Group War History, Volume 2. It specifically covers orders and deliveries from December 1942 through November 1944, though there are totals that go back to 1939. Volume 1 (1939 through November 1942) is no longer extant, and it's not known if there ever was a Volume 3 (covering December 1944 onwards).
Rootes Wartime Orders & Deliveries