They dolls that can be gained are:
-Surf Pikachu Doll
-Gold Trophy(not a doll but a decoration)
-Silver Trophy(not a doll but a decoration)
-Big Lapras Doll
-Big Onix Doll
-Big Snorlax Doll
They can be gotten from your mother buying them with your money(when you allow her to save up your money) but they can also be gotten from mystery gift transfer from Pokemon stadium 2.