Onuschak seems to be a Rusyn surname.
Written in Polish - Onuszczak
in Hungarian - Onuscsak
in Rusyn - Онущак (Onuščak)
Polish Galician Onuszczaks come to America from Hańczowa.
https://maps.google.pl/maps?q=Ha%C5%84czowa&ie=UTF-8&...

Among Rusyn surnames was Белей, in Polish Bielej, in Hungarian Belej.