Green’s Dictionary of Slang

1. (US) to meet by accident.

1938		J. Weidman I Can Get It For You Wholesale 9: You bunk into somebody, and it brings you up cold.
1943		J. Mitchell McSorley’s Wonderful Saloon (2001) 124: The best time to put the bite on them is to bunk into them at a funeral.

2. to knock against.

1953

F. Paley Rumble on the Docks (1955) 22: In the early morning darkness, they were always bound to bunk into a shenango.