You might take a look at the Hyosung GV250 (or the United Motors 250T, same bike). My wife has one and it’s a little larger than most of the other 250’s (such as the rebel, nighthawk, vstar, etc). She’s had this one for getting close to a year and has had no problems with it at all. However, since they’re relatively new to the US market, I’d personally only recommend getting a new one if you have a reputable dealer & service center in your area. And that being said, being 6’3″, you might sitll be cramped on it. Would something like a Vulcan 500 be out of your price range?