In the "Why didn't I think of that" catagory, here's someone relic-ing new cases to look old.
http://relicguitarcases.yolasite.com/
I have a pre-war conversion that has authentic patina but looks really out of place in a new case. The Lifton and Geib cases from the 50's look more age appropriate that a shiny new one, but they have astronomical prices on Ebay. The old ones also suffer from aging, loose latches, worn out handles and usually a funky beer-cigarette-cigar-and-who-know-what-else smell.