[APKhaos]

Doug is hot on the trail.......

In the [very] old days, the radio console contained the volume, tuning, and power controls only. The rest was too darn big to fit in the console. What I think you have there is the 'remote' side of one of these early radios. It contains the RF stages and audio amplifiers, all of which were hollow state technology - vacuum tubes.
If you can find a becker model number anywhere, the 'men in plaid' might be interested - many early 356s had these ripped out in favor of the later on-piece transistorized units. This might be a nice find for the true 356 resto fiends.