I don't know who the maker is, but the same backmark is seen on this 'Lyre' ball button, said by the seller to be an 1800s band/musician's coat button:
I believe the Ebay seller is seriously incorrect about his Lyre/Musician's button's time-period being 1800s (as is very often the case with Ebay sellers). Note that the button's backmark is written in "plain block" lettering instead of the usual 1800s "serifed" lettering. We button-collectors see very-very few plain-block backmarks prior to 1890. But the killer time-dating clue is the "hollow star" mark. In a button backmark, that is strictly 20th-Century.