459 = burglary.
Bunco refers to the fraud squad of a police department. Bunco was originally a confidence game similar to three-card monte.
One of the few instances when the use of a two-way mobile radio is seen, in this case by Mac at the mine shaft, and by Malloy in the unmarked police car.
KMA-367 was the official Federal Communications Commission (FCC) call sign for Los Angeles Police Department radio transmitters from 1948 through the 1980s (Los Angeles Almanac).