backlight bulb for digital aircon display on synergie

[Mosser]

The backlight bulb on my synergie's digital air con display isnt working, and i can only see the temperature at certain angles when the sun shines on the display which usually means i just press the + button a few times if its too cold, or the - button a few times if its too hot !!,

It would be nice to get it working again, but does anyone know what type of bulbs they are ?, and where to get them ?, and possibly how to fit them ?, I'm hoping the whole dash doesnt have to come out ?

Thanks