A safe bet would be it they use regular aux power, 14-16vac. One on ebay looks like a little wheat grain bulb, not LED. But, verify if that's true.
Here is from another listing I found:
G Scale Model Power Round Street Lamp #984
New in Box
9" High
Clear Light
Plastic Base & Topper
Gray Bass Pole
2 wires in circular base to connect to A.C. power supply terminal
compatible with 12 - 18 volts
ADDED: Look on the package.