A child's Baseball Uniform with the name Cardinal's on the front/ Post Mfg. Co./ New York. 1950's era. Approximately size 4/5.

This is an authentic Baseball uniform for a child. It says Cardinals on the front. Approximate size is for a 4 or 5 year old. It was in the family which was located in St. Louis, MO. It has been in my house for 40+ years and i know nothing about it. Inside the Jersey, there is a tag which says Post Manufacturing Co./ New York. The pants have no marking.

It looks so 'real' and I believe may have been bought by my Mother-in-law many years ago for one of her three sons (or all of them may have worn it at different times). Possibly St. Louis Cardinals Baseball team (when it existed).

I would like to know as much as possible about this.