Masters of Victorian glass engraving

I bought this recently and was trying to look up the lozenge registration mark. I couldn’t decipher the months and years!!.. It’s class 3 for glass…..but I would love some help with the rest. I am trying to work out the maker by the year and what was produced. I thought the right side mark was a B or an H. There is no letter B for the 2nd category of dates….. I believe it to be Stourbridge, Could be Webb or Richardson. Any ideas please??