New user help needed with dated silver spoon

So my mother has a silver serving spoon, with hallmarks and engravings. She said that it was passed down from ancestors. Apparently, a whole canteen of cutlery was made for a wedding, and it’s been split up, and I’m hoping to find more information, and maybe reunite some of it.
On front of spoon is a capital A, on rear is ‘T G’ and ‘B G’ then ‘Oct 5th’ then ‘1775’ (the date of the wedding, presumably) hallmarks on rear not very clear, but I think one is the silver Lion, one could be a letter B or g, one could AB.

Photos on photobucket

The hallmark on the stem of the spoon appears to be a London mark with the date letter S for 1773. I am unable to make out the maker’s mark because of the quality of your picture. Can you take another picture without flash and in focus. It is not important to have such a large picture as you have posted but it must be in focus. You will have to support your camera on something fixed as it will require a longer than normal exposure.

Thank you for the reply. The photos were all I took on my phone, and I’m not at my moms, I’ll have to see if she can take any more photos, and send them to me. I’ll reply when I have them, thanks again.