I agree with @DylansMom, you probably won't have any trouble joining up chicks that are within a couple of weeks of age as long as it's just chicks and not adults involved. I've had chicks hatching since the end of February -- it was those darned heat lamps in the pea-shed -- but mostly in ones, twos and threes, so I've had to add chicks, rearrange chicks, and swap chicks in and out for 3 months now, and it's gone okay most of the time. I had one chick that was only a few days old start savaging a newly-hatched one, so you do have to watch closely, particularly at the start. Try to avoid big differences in size. I noticed that once they had been through the roommate adjustment, then moving up with bigger chicks or adding smaller chicks wasn't as hard as the first meeting with other chicks. There's a learning process getting adjusted to flock manners.
That's great to hear. I may try to see if I can find some more then, just to increase my odds a bit.
I did get both the peafowl and pheasant eggs last night, no broken, air cells appear to be good. The pheasant eggs were especially beautifully packaged, Styrofoam inserts.