Im guessing you dont have it apart yet. I would take it out, if you dont already, get the number off the bulb, and count how many you need, then order a few extra, they are cheap.
You can probably search the forum and find pictures and bulb info....I dont have factory gauge cluster anymore, so I dont know. While you at it, order LED bulbs for all your other bulbs, side markers, dome, brakes, etc. you wont regret it.
For LEDs you want T10 (base) SMD (surface mounted leds) 12v and a minimum of 10 diodes each unit. might go with 12 - 14 for colors. Search hard and find lots of 10 or so for not a lot of money, pick the color you want. You want the ones that look something like this: