Best place to buy '60s Mustang?



So I'm a new age, tech savvy, environmental type. I drive a hybrid at the moment, got a Telsa on order and often use electric Smart cars on days like today when I'm just shuttling round Amsterdam and surrounding areas.

But, at the weekend, I've got myself hooked up with a bunch of crazy petrolhead Dutchmen (and a couple of Belgians) who like to ride around in '60s/'70s American muscle cars. Touring round the country, occasional track days at Zandvoort and other tracks.

So I'm thinking of buying one but they are crazy expensive in Europe so I'm thinking of importing from the US.

Right now I'm thinking 67-69 ish Mustang fastback, nothing crazy, just the standard 289 (the Boss version are silly money). Doesn't have to be immaculate but has to usable with some tinkering not a full resto job. Need to be auto because of my dodgy leg.


So where's the best place in the US to look?

Other suggestions for suitable cars, maybe a bit off the wall?