Pinball flashers or Pinball blinkers

If the bulb in your game is flashing or blinking, it is probably not a "flasher".

Pinball flashers are 12v bulbs designed to highlight important activities in the game. These are typically #89, #67, #66 or #906 bulbs. The game software controls the flashing effect. The flasher bulbs are typically brighter and powered by higher current to really stand out.
Pinballbulbs has its line of LED flashers here:

On the other hand, pinball blinker bulbs run off a normal 6.3v circuit. The bulb, itself, blinks when powered at random intervals. Blinker bulbs are often referred to as "twinkler" bulbs. The blinker bulbs are #545 or #455 and come in a standard #44 or #555 base. These bulbs are smaller and look like standard pinball bulbs used for general illumination or insert lamps. We have blinker bulbs here: