From the website that Otto linked:
"Your 1950 Chevrolet All Models is painted at the factory with a high quality basecoat/clearcoat system. This two-step paint system consists of step one, the basecoat, which is your car’s actual color, and step two, the clearcoat, the specially formulated clear paint that protects the base color and provides the luster and deep shine your vehicle came with when new."
If their touch-up paint is base/clear, then it WON'T match the factory paint system (color could be correct though.) I don't believe anyone used a base/clear paint system back in the '50's.
A good automotive paint supply store can put single stage paint to match your truck in a rattle can for you. You'd just need the paint code to match the Forester Green. From Tim Lederman's Tech Tip on 47-55 truck colors
HERE Forester Green would be PPG 40519 or Dupont 62006.