How to find Vce SAT in NPN transistor datasheet
If you look at the Figures 10, 11 and 12 you can see a set of graphs for Vce vs collector current at various base currents. Choosing the 4.8mA base current curve as being closest to what you want, you can read the Vce value at around 150mV - 200mV for all three of the transistors at 150mA of current. This is quite typical for a BJT device in saturation.

Note that in practice there is quite a lot of variability in this value between parts/batches and it will change a bit with temperature (as you can see in the other figures 7, 8 and 9).