1 year old is not to old. Technically, that dog is still a puppy. An older puppy, I grant you, but still a pup. Dogs aren't considered adults until their around 18 months.
I would only get the dog, if I felt it was a good fit for my home. I will say, that the age of the dog would have no bearing on whether I brought it home or not.
BTW, my first dog, was a rescue. She was about 1 1/2 years old and someone left her tied to a fence...abandoned. This dog bonded very tightly with me and became my agility & obedience partner. She lived to be 17 and was just a fabulous dog. I'm glad I took her and kept her.