It seems to be very hard to get hold of the switches with the white toggle, which is accurate to the movie prop, though I have come across them occasionally after much searching. I can't find any easily right now. But you can get similar switches with black toggles, and I've used these in the past. The size is the most important aspect, obviously. You're looking for a 2-position mini (or micro) vertical slide switch measuring around 8mm x 4mm x 4mm.
Something like
these (in the UK but there'll be equivalents elsewhere I'm sure).
The tip of the toggle will then have to be painted white if you want complete accuracy. Hope this helps!