The rectangular Peavey case of the late '70s seems to be the basically the same as that used for many other basses of the period, e.g. the Ovation Magnum (I have both). Besides being unnecessarily bulky, its main shortcoming is that the little screws on the inside that secure the handle to the aluminum profile around the case are liable to come loose and drop out. They can be tightened if you manage to pull the edge of the plush-lined interior panel back. Superglue is useless, since aluminum oxidizes so quickly.
Without a grip the case is totally unwieldy, so it was a good idea to integrate the handle into the design itself, as Peavey did with the later, wedge-shaped model.