Hi Guest :)
What a terrible Sad story :( :( Poor puppy.
Legally I have no idea where you stand. How disgusting that a breeder makes someone sign a contract like that

Absolutley no reputable, honest breeder worth their salt would ever do that

Unfortunatley, these puppy farms will always exist as long as people buy them (and that is no slur against your mum). When I was first looking for my pup, I rang all these kind of kennels, looking for a boxer. Luckily I stumbled across Champdogs and realise very quickly what I was doing. I learnt from here and now have a beautiful Boxer girl, from a very decent breeder who will always be on hand.
A good place to start in your search is the
Labrador info on Champdogs. It will give you breed guides, clubs, useful links and the owners/breeders registered with Champdogs. Talk to as many people as you can. Ther are many experienced Labrador owners/breeders who can give you excellent advice.
Good on you for learning from that unfortunate experience and wanting to put it right.
I wish you luck and hope you find the pup right for you.
Ali :)