For non Portal fans, what he needs is a way to alternate between a group of orange and blue LEDS. These LEDS stay lit during the operation of the toy and don't require any special effects.
I made a small illustration for the light system, you can build it using some LED flashlight guts and the indicated switches.
However, for the sound system you will need more electronics knowledge (i.e. how to use a 555 IC) and soldering skills. Or find another toy that sounds in the same way, you can take the circuit from it.