It is a magical bug, that will allow the owner to hear what is said in the immediate vicinity of the “bug.”
Once two or more matching helms are found and worn, they enable the individuals to communicate like they were standing next to each other. The helms transmit all sounds including the surrounding noise and at the same volume as the original.
Itching dust makes someone or something itch. It is very distracting and only gets worse until the dust wears out or an antidote is applied.
Wearer of this shirt can walk unnoticed into almost any even/gathering/bank and perform just about any action without being noticed. Only extremely out-of-place action will get the wearer noticed at all.
Patterns in surnames: There are many ways a surname could have evolved over centuries. One possibility is migration. A Roman name may have traveled to France and hence to England where it was later Anglicized. Case in point - the surname Lawrence went from Laurentius (Roman) to Laurent (French) to Lawrence (English) and then to Lowry (Scottish). There is also natural etymological evolution. For example, a Middle English spelling may have evolved to a modern English spelling (e.g. Stiward to Stewart). Where did your character's Surname come from?