These will have been standard fonts. You just need to find out what they were, and then find a similar one and install it on your computer.
Here's a nice 40s style sans serif font to start with:
http://www.dafont.com/keep-calm.font
Gill Sans was widely used, but it is a commercial font and you have to pay to use it. Free clones are available.
https://en.wikipedia.org/wiki/Gill_Sans