Could someone help me with this hallmark

I have recently recieved this as a gift and i was interested about the origin of the item. I have identified three of the silver hallmarks, meaning that it is 1st standard and was made in London, although i cannot find the meaning of RWB. I would appreciate if anyone could help.

“First standard” has no meaning with regard to British hallmarks. I suspect that you are reading the date letter l (lower case L) as the number 1. The hallmark has the lion passant for sterling silver standard, the leopard’s head uncrowned for London (as you have correctly identified) and the date letter for the assay year 1966/67. RWB is the sponsor’s mark and is the mark of Harrods Stores Ltd, RWB being the initials of the company chairman, Richard Woodman Burbidge.