My dad built these for me in the early 2000's.
LDD file included!
About this creation
These cars were inspired by two 4.5V sets: set 7722 "Steam Cargo Train, Battery"'s mail car & set 7715, "Push-Along Passenger Steam Train" and it's two passenger cars.
I added a passageway through the front of the mail / baggage car to allow the conductor to do his duties and made the bright colors of the original train more subdued with good ol' Brick Railway Systems black with a red stripe.
The rear of the baggage car has room for the letters BRS, standing for Brick Railway Systems.