Hi and welcome to the forum.
This is certainly not a Birmingham hallmark. However neither is it a fake mark, rather an example of what we call a pseudo-mark. Fakes are deliberately created to deceive the customer. This, though coming close to the line, is a (probably) American manufacturer attempting to use the kudos, reputation and perception of a genuine hallmark to show that his product is top quality.
I don't recognise the maker's mark of T in the lozenge.