Woodbridge Antiques has dated this piece to the 1920s.
The maker's mark is also very clear for the renowned silversmiths: R&W Sorley.

A fine Christening tankard and a good heavy gauge of silver. It would make a great Christening/new baby gift!
Condition: In great antique condition.
Hallmarks: London 1929 by R&W Sorley.
Measurements:
Height: 8.5 cm
Diameter width at rim: 6.6 cm
Width including handle: 10.5 cm
Weight: 172 grams
Weights and measurements are approximate.
Woodbridge Antiques has dated this piece to the 1920s.
Specialists in quality antique silver, fine jewellery & accessories
You can view the stock and full dealer information on the Woodbridge Antiques Profile Page