its more of a copyright issue, you can get many at the library of congress. if it's over 70 years old, i think the drawing itself can be used, i don't know how it works with making the device. maps have i think a different rule, but you would have to check into that. if the images are a certain age, or if the govt made it, then its usually ok. according the library of congress, they wait 130 years for anything outside the US to deem them safe to use.
---Mike Savad
MikeSavad.com