Mike, you are looking for a performance cruiser. I built one for my wife about 4 years ago. Though I didn't shoot for a weight target that low, I did end up with a lighteweight bike with cruiser ergos. You won't be able to buy one. You'll have to build to some degree. What is your budget? Can you do basic wrenching like swapping handlebars and changing stems? You'll likely have to buy a new saddle as well.