This unique circular bank is located in a small Long Island hamlet of Albertson. Thanks to this website for alerting me to its existence. And although photos may not be allowed, I went by on a Saturday so I was able to get at least one interior shot of the center light well. No idea if this light fixture is original or not.
As the other website states, this was originally Reliance Federal Savings and Loan, built in 1967. According to the book, An Architectural Journey Through Long Island by August Viemeister (Associated Faculty Press, 1974), the architect was Siegmund Spiegel who was based in East Meadow, NY. He was a draftsman for mid-century firm Mayer & Whittlesey as well as a German Jew who fought in WWII.