@heavanet- There aren't many places that are good sources for finding vintage musical instruments. The key to finding one is shopping at a place that knows musical instruments. Second-hand shops are not notorious for selling this kind of merchandize.
There are many musical instrument retailers that specialize in vintage instruments. Not only will you find a large selection of saxophone from a reputable dealer, but you will have the peace of mind in knowing that the information you get about the instruments is factual.
If you don't have this type of shop in your area, you might have to search online. Though you are likely to find many vintage instruments for sale, you shouldn't buy one without seeing it in person first. A reputable seller will be more than willing to let you take a look and try out the vintage saxophone before you buy it.