Efficiently driving 8 low-current Optocouplers
Look at the ULN2003 and related parts within the group darlington arrays, they're good for driving LEDs, small relays, etc. well over your current and power dissipation requirements.
They're probably even overkill for such little currents.  

Check out the use of a octal buffer or transceiver such as the common 74HC244 though instead of "HC" you may want to use a different part depending on your MCU's Voh/Vol logic levels and supply voltages vs. the required LED supply voltage.  If the minimum needed LED anode voltage is sufficiently high (e.g. higher than the Vio/Vcc rail of your MCU / buffer IC) you'll want to choose a buffer that can have perhaps a higher output voltage (>= LED anode voltages when they are off) while maintaining logic level compatibility with the MCU LVCMOS or whatever output levels.

You could also use an application specific standard part which is a purpose built multi channel LED driver, for instance, the TLC59282 or numerous other 8 channel or 15 / 16 channel parts intended for the purpose.  Many of those will be able to save MCU I/Os by interfacing to the MCU via a shift register or similar system if that might be useful.