Souvenir 20 (Jug of Milk) and 21 (Smoothie) can be gotten from the middle town at the station (the name escapes me right now) and going into the convenience store there.
I found how to get souvenirs 22-24 (the hammer, drill, and ladder). From the station go to the first town and the only place currently open (the hardware store) and all 3 are in there.
