Your skill in 3D modelling is extraordinary, caution. You know, once in a while one comes across a boombox being sold on eBay with a battery bay lid that is lighter in colour than the rest of the rear panel (or underside or whatever) of the portable unit.
Of course, the lighter-coloured "snap in" lid could be from a lighter-coloured model of the same brand. Or from a lighter-coloured model of another brand. (James Craven Pierce, AKA DecentMan4you, once demoed the interchangeability of a battery lid for several boomboxes' battery bays. It was in a YouTube video that he apparently filmed to answer a question of mine, here or on Stereo2Go. The portable units were face down as he clicked a single battery lid into place, lifted it out and then snapped it into place over another boombox's battery bay.)
Anyway, I now wonder, could those pale-hued battery bay covers have been 3D printed by our caution before helping to sell an Aiwa, a Sony or the like? Thanks for sharing and advising.