Oh no, I'm so sorry for the loss of your sweethearts. I remember when you got them, your wonderful nursery set up. How your dog dressed up. I know how much you love your ducks - just like I love mine. I know how special they are and how much it hurts to say goodbye. 3 in such a short time is too much.
If you get ducklings you might have more fun and bond with them better, but your pekin would probably prefer an adult duck or two. She'll have to wait a few months for ducklings to grow up to really be companions.
I have adopted adult ducks twice. The first time my existing 2 ducks accepted the 3 incoming ducks like they had always belonged. The second time my existing 5 ducks rejected the incoming 1 duck. The incoming duck longed to be accepted, and after several weeks my existing flock stopped pecking at her but they never welcomed her into the flock or loved her. Since ducks are individuals they don't always get along. That doesn't mean you shouldn't try. I just want to give you realistic expectations.
I would like to share that I got a virus and parasites in my flock by adopted adult ducks. They had been abandoned on a pond and we're swimming with wild mallards. I don't regret adopting them as they would have likely not had medical care without me. But I feel like you might want to consider this and only adopt from a private home with good biosecurity practices or ducklings from a hatchery.
