Hello!
There is a company called A.I.T.M. that makes and sells resin parts that allow you to build your own truck, and they have many designs from the 40s and 50s:
http://aitruckmodels.com/shop/
Like this baby:
Be warned - a model like that takes a lot of money and skill too - you have to do a lot of research and build many parts on your own.
I hope it helps you - have a nice day
Paweł