I think one of the main influences on the flapper revival in the late 60s was actually the Bonnie And Clyde film that came out in 1967. If you look at Linda's post on page 3, there's the picture at the top of the Yves Saint Laurent outfits. The "smoking and city pants" in that picture came out in 1967, and I would say that is very heavily influenced by the film. A little higher up is the exterior shot of Granny Takes A Trip which was taken around the same time, and again it's the gangster look influenced by the Bonnie And Clyde film. There really was a huge fad with the fashions in that film when it came out, and I'm sure that people went looking for more fashions in the past, found the flapper style clothes in all the new vintage clothes markets springing up everywhere, and the look evolved.
To be honest, I think the styles of fashion from different eras are heavily influenced by the shape and size of the people from that time. The British youth of the 60s had all been born while rationing was still in place and that affected the way they grew, and it was well into the late 70s before people started to fill out again. So for that reason, the 60s look is sort of created for these tall, thin, stick-insect people that don't really exist anymore. There's a lot of 60s fashions that don't look right on me as my chest tends to be too big or my bottom sticks out, so it really is just a case of trying things on and seeing if you can get away with it. The 60s is a very difficult era to try and find wearable clothes for, so I'm afraid I have no magic answers as to what will suit you, it's just a case of trial and error. Having said that, the geometric style - which creates it's own shape and takes almost all emphasis away from the actaul wearer, might be a good place to start. There's a good chance you could manage something like that. I'd also try quite a few different designers as they all make clothes to fit a set shape, and there's boung to be one somewhere that was your shape. Designers were more sensible back then, they didn't expect everyone to be the shape of Naomi Campbell or Kate Moss.