The brand name SONA for metal teapots, milk jugs etc made back in the 50s and 60s is derived from Stratford ON Avon where the manufacturer was located (the site is now housing, a BUPA care home, a Travelodge and an ALDI) - the similar products under the SWAN* brand were also made there.
*Swans are very much associated with SuA with the fearsome things on the river, one of the theatres, an orchestra and the Black Swan pub (a.k.a. The Dirty Duck)