Tonka Winnebago Indian replacement refrigerator door.
Mine was missing so I have no idea how the original was attached, but this grooves into the left side and catches on the clip on the top right. Fitment may vary depending on how the plastic has aged so I'd recommend doing a rough draft test print first in case you need to rescale to fit yours. Printed in California Filament orange PETG which is a decent match to the original orange interior pieces.