Using a Optocoupler - Determining Parameters
380 ohms in series with the input, driven from 5v, will be just fine for getting approximately 10mA into the input LED.

The min CTR (current transfer ratio) is 750%, so with 10mA in the LED, you could expect to sink at least 75mA in the output. With a VCEsat of 1v, that's an output dissipation of around 75mW, which with 10(ish)mW on the input LED is within the package limit of 200mW. However, that limit is at 25C, it will drop with temperature.

The data sheet doesn't give a maximum output current anywhere. In figure 4, the curves only go to 40(ish)mA and are curving quite quickly, so that is a hint at what the manufacturer's expect. The package dissipation limit will give you a bound on the output current, much above 75mA as calculated above will be getting close to that at an elevated package temperature.