Poodle mixes can be great dogs. I've liked most of the ones I've met. Although we do have one client at the vet where I work who has two. The older one is fine, but the younger one has severe behavioral problems that she had to go to a behaviorist for starting before the dog was even a year old.
7 weeks is too young for any dog to go to a new home, no matter what line anyone tries to sell you. Almost all dogs are fully weaned by the mother by the time they are 7 weeks old, many by the time they are 6 weeks old. It isn't weaning that is the problem. The issue is that there are a lot of important things that dogs learn from other dogs before 8 weeks of age, and removing a puppy from the mom and litter even a week or two early could potentially set you up for some pretty bad behavioral problems later in life as the dog has missed out on important lessons that they learn from the mother at that age. There are enough studies and enough evidence to back this that it is illegal in most places to sell puppies that are less than 8 weeks of age. It doesn't matter that x many "breeders" say it's "fine," it's still illegal and those breeders who do it are breaking the law. With large breed dogs (and at 50lbs, the parents certainly count as "large breed") it's actually ideal to leave the puppies with the mother until they are 10-12 weeks old. Puppies that stay with the litter and mother until at least 8 weeks (and in the case of most larger breeds even longer) tend to develop far fewer behavioral problems. So, if they're going to let her go at 7 weeks, you had better have a darn good trainer lined up and plan to take this dog to multiple/ongoing training classes (as opposed to just a 6 or 8 week basic puppy obedience class). You should also plan to spend a lot of time socializing her around lots of different people, places, and objects to avoid fear-based aggression issues (that's just plain good advice for any puppy, but it is especially important in puppies that are allowed to leave their litter too early...ie before 8 weeks of age).
Good luck! Poodles have a reputation for being "fru-fru" purse dogs, but they were originally bred to be sporting dogs and they have a lot more energy than most people realize (especially the standards). And goldens are crazy full of energy as puppies and young dogs. You're in for a wild ride, but I'm sure the joy she brings to your family will make it all more than worth it.