Thinking about a change

IMHO I would look for one of these
68,69,70 RR
68, 69,70 coronet super bee
68-69-70 charger
70,71 barracuda

I think 70,71 challengers have been done to death, but that's my opinion. And possibly because I see so many new ones on the road.

Those would all double my budget for sure. The 66-67 Chargers are still pretty reasonable for b bodies. They are an acquired taste for sure but I am a sucker for fastbacks.