Welcome to YorkieTalk!!
I personally feel that 8 weeks is too young to let a puppy go...Most reputable breeders will keep them until 12 weeks. They learn so much from their mom and littermates during this time. There's no way that the breeder can guarantee weight. According to the breeder, (who later I found out was actually a broker for puppymills
) my yorkie was supposed to be 4-5 lbs...He's 11 lbs
Honestly, I would keep looking...If you want a small one, I would find a very reputable breeder who happens to have a small one, not a breeder who purposely breeds 3 lb females to get smaller ones...
Try
www.ytca.org