I just had a look at the service manual. I see bulbs in there, labeled "DS2" and "DS3". "HRS-7219A". These are 3mm 12V incandescent bulbs, which were commonly used by icoms of this vintage. They burn out.

I just replaced these in my IC-820. I used "warm white" 3mm LED lamps, and coupled them with a resistor to work using the 7V to 11V input. The result looks pretty close to stock.

Here are the LEDs I ordered: https://www.amazon.com/dp/B077X959CG

You'll have to judge fitment for the IC-229. The IC-820 had plenty of room to mount the LED and resistor.

Good luck.