Ok first i would like to say something about the "Friendly ducklings" idea. I have never had a friendly Pekin. The friendliest duck i ever had was a male rouen and he would run up and bite my shoes. My ducks never liked being held.
1. Ducklings normally end up soaking their chicken roomates so its generally a bad idea to have them in the brooder together.
2. My Pekins actually lay year round. They do slow during the hot months and they enjoy making nests where i can't find the eggs, but the laying is almost non stop. If thier not being broody you can eat all the eggs just like chicken eggs.
3. They might go broody in the spring. Their kinda young right now and will produce nice fertile eggs later. The eggs may be fertile now(if they are laying any) but i tend to wait so that both parents are fully mature.
I know people say they aren't broody birds but i have one pekin duck who will sit for 6 months out of the year. I actually wrote a forum about how to "trick"/condition your duck's pen to encourage her to go broody. I think i called it
Breeding Ducks. I believe
Goatwalker followed my advice on that post and actually got his buff duck to set.
And finally i vote you get the adults. Pekins make WONDERFUL mothers and even if you can't get them to breed you will have some very nice birds. Besides you can always slip a few of their eggs in the brooder and be a selfMade mama duck.