Robert Barron did not trade from the Strand. That was the business of his father Francis Barron Snr. After his death, only Robert’s older brother Francis Jnr continued to trade at the Strand.
Robert married and moved to Hoxton, then traded from 66 Barbican. and later nearby at 75 Wood St, Cheapside.
As to when the OP’s padlock was made, who know? seemingly Francis Jnr and Robert cooperated, and both seem to have made some of Robert’s patent locks. This design, however, seems never to have been patented. Such locks in various sizes continued to be made through the 1930’s.
Btw, Robert later also invented, but did not patent, a form of fly-talon lock. This proved inconvenient for users, and seems not to have been much of a commercial success, although some were used by London cabinet makers.
