After much searching I have found the part # for the illumination Bulb used in the cruise control switch, Fog light switch, and other dash switches.

This I know works in 93-01 Impreza , 02-05 Impreza, and also 91-97 SVX.

Subaru part # 83426AA040 BULB ILLUMI

umm ok?

or you can buy one from radio shack.

LED option? lamp size?