its looks like a T5 bulb
O.T - i had to replace that bulb in my meter cluster once and i bought a flat LED T20 bulb and removed the back casing and welded the bulb inside the small hole.
but after i did that, i found these bulbs for sale in a few shops in kandy.
just saying, if you cannot find a bulb, welding a T20 bulb is a option as well.