There are a lot of vintage bikes you can find, but you have to know a lot about components from that era so you know if you're getting good components, you also have to be sure that when looking at a vintage bike that it has all the factor original components, some people strip the vintage components off put on cheap modern stuff and then sell the vintage components for a nice profit while telling people they have modernized the bike hinting that it's now better then before, not true, plus it ruins the vintage value of the bike.
There are quite a few nice new bikes you can get for under $1,000, there is even one that has the classic look called the Raleigh Grand Sport that's less than a grand.