Correct me if I am wrong...but isn't AA traditionally used by USA and not Birmingham?
As to the value of your piece....the maker is very small or unknown to the major lists of makers. However, here is very good advice about the value of your silverplated items:
Silverplate flatware contain such little silver that is has no scrap value (silver overlaid upon another cheaper/less valued metal - Silverplate at is thickest point is only about .20mm or 8/1000th of an inch thick.). So, it's not cost effective to melt them down/recover it...costs more to process than what is recovered. So, unlike sterling, the resale value is not based on silver content.
However, these pointers do help in deciding the value....
Condition, Pattern (unique?, popular pattern and is it easy found for people to add to their sets? The harder to find the higher the asking price.), Rarity (collectible item - uncommon pieces other than traditional place settings)
Remember PATTERN MATTERS A WHOLE LOT!!!!!!!!!!!!!!