Monarch was the brand name for Eclipse Radio of 21 Sturt St South Melbourne.

They also had the Peter Pan brand name.(note the similarity in the enamel badges)

Their first Bakelite model was the Monarch EG it was a re-badged Astor Mickey Mouse model EC (with a very dull plain boring cabinet)

The model GKL (above) is quite original and came in the usual Astor colours.