What's the voltage applied to the bulb? With that (and assuming it's at least 5V) you should be able to calculate the required resistance of current limiting resistor to deliver rated (desired) current thru the LED. Don't forget a white LED has perhaps a 3V junction drop -- check the data sheet for the desired LED.
For example if you have 12V, an LED that requires 20mA w/ a junction drop of 3.0V then you need to get 20mA at 12V-3V=9V of drop across your current limiter so you need a 9V/0.02A = 450 ohm, 1/4W or 1/2W(9V*0.02A=0.18W) limiting resistor. A 470 ohm would be close enough. http://www.icom.co.jp/manual/external/transceivers/IC-211.pdf
indicates that the meter lamps *are* LED's however.