This is a London hallmark for the assay year 1945/46. Unfortunately we will never now the maker’s name because LAO is the mark of the London Assay Office itself. This mark is used where the maker, for whatever reason, did not have his/her own mark.
Thank you Phil,is it worth anything do you know.
It’s silver so it must be worth something. If you can find something similar on Ebay’s “Sold” listings that will give you an idea of how much. At a minimum scrap .925 silver is selling for about £10 per ounce.