Tru-Scales are way cool. Not cheap either. You found a pretty decent one. They are in there with the early Ertl replicas. A smaller scale than the other pressed steel trucks with authentic details, more of a promo than a toy. Did you check to see if they made your tear replica?
Ok, I just checked and it looks like they held off changing from the A-series till '59. Looks like they made one version of each body style in the years they were in production.
https://www.google.com/search?q=57+t...w=1366&bih=631