I bought a second hand Schoema which was missing one of the Lamp covers, so I quickly printed a replacement.
Printing details below.
Edit: I added a small extra piece which you can insert at the bottom at the lamp to hold a standard 5mm LED instead of the old light bulb. That way you might get along printing the lamp with PLA.
Supports arent really needed, if you have a good part cooling, but they help to get a nicer surface of the inner side of the lamp.
I printed my test version in PLA, but I would recommend something more temperature resistance, as the old LGB lamps can get quite hot.
PETG, ABS or best ASA, if your trains stay longer outside (UV resistance).