The original script treatment, as seen on DVD 3 of the "Ultimate Toy Box" special edition, had the original star of the film (Tinny the Tin Toy) coming alive in the factory before being shoved into a box.
Our story opens in a small factory where tin toys are manufactured.
They sweep down a conveyor belt with all types of other toys of
different sizes, shapes and colors. We single out a group of tin toy
musicians, then we focus in on one, our star, Tinny.
His eyes are opening up and he's looking around, wide-eyed with
excitement. The conveyor belt goes to the shipping area where he's
boxed up and put into a big carton. As the box is folded up, we follow
him into the dark.
In the second version of the treatment (described here on p28), his origin is the same but he comes alive when his carton is opened in the store, ready to put him out for sale.
Tinny was no longer born in the factory; he was born as he was
unwrapped. The ventriloquist’s dummy was already in the house, and it
was the children’s favorite toy. The dummy became jealous of the shiny
new Tinny, and they started to argue with each other.
This tallies quite nicely with the Al's Toy Barn scene in Toy Story where we see the rows of Buzz Lightyears talking and moving in their packaging.