I agree she's a pullet, as for the other ones. I have 2 nine week old australorps and I've been google imaging them for weeks! I've seen roo's have pretty big combs from 4 weeks and I definitely think at 7-8 weeks a roo would have a lot more comb and be wayyyy redder in the face!
Thanks so much you guys!
I'm glad. She was the single one I brought home (after already buying 6) because out of the bin of flooded black, had an extreme amount of white all over her face and body. So, obviously, had to have her. It's the first time picking the 'odd one out' now has me a hen! Yay.