Rear light, original from Honda Stanley. Commonly used rear light, for example on: SS50, C50, C70 & C90. This is the version with a mirror behind the bulb. The price difference is certainly as big as the quality difference with a replacement part!
This rear light is also common on 1970s Honda Motorcycles such as: CB125, CB250, CB350, CB400, CB500, CB550, CB750 etc?