Best has explained that "Fujiya" refers to Fujiya, a Japanese manufacturer of record players, and "Miyagi" refers to the character of Mr Miyagi from the film The Karate Kid, because the two names together "just looked really nice written down.
Best has explained that "Fujiya" pertains to Fujiya, a Japanese record player manufacturer, and "Miyagi" corresponds to Mr Miyagi from the film The Karate Kid, as the combination of these names "looked particularly appealing when written down."