Therapy Dog

Dear Friends
I am hoping you can give me a hand-
As you know, my beloved 13-year old lab, Sierra, had to be put to sleep last week.
While she had not been evaluated to be labelled a "therapy dog", she basically was.
She frequently joined me in therapy sessions and was often integral in getting my young speech clients to sign, verbalize and demonstrate turn taking. This was especially true for children with ASD and/or apraxia. A few of my favorite memories when working with Leelo (my 8 year old client and friend who has autism)and Sierra are:
When he played fetch with Sierra and his Mom, "Squid", told me he had never thrown a ball so well before. He then continued the turn-taking routine with her for a number of turns.
More recently he became interested in crouching beside her and imitating her.
He enjoyed seeing her "sit" and "lie down" in response to his verbal commands.
During one of our weekly sessions he appropriately asked for her (she was not there that week) by saying, "The Doggie?".

I am looking into getting another doggie.
My hope is to get a dog that can become a certified therapy dog and be an integral part of my speech practice (and of course my family). I am partial to labs and bigger dogs and prefer a female. I have also looked into Australian Labradoodles (of course half the fun there is I could name it "Dude"). I need a dog that is easy going, mellow and easy to train. The difficulty with getting a puppy is you do not know what the personality will be and it takes a while to train them. I would appreciate and leads or thoughts any of you might have on a young dog or puppy that could join me.

NOTE: I have contacted Canine Companions and was denied for a facility dog as they prefer to place dogs in large facilities. I have met with similar road blocks or huge waiting lists with other similar organizations.
Please pass on any good tips!
Please email at: sageslp at gmail.com