If I was looking for a vintage cyclocross bike, I would try to find an old Ritchey Swiss Cross. This was one of my Holy Grail bikes for many years but I never succeeded in finding one in my size. Meanwhile, Ritchey reintroduced the Swiss Cross, so you can buy a new one in just about any size. Ritchey also makes a Breakaway Cross, which has similar geometry to the Swiss Cross but the frame can be broken down for traveling, and it also has mounts for fenders and racks. I bought a used Ritchey Breakaway Cross a couple of years ago, but it's not old enough to be considered vintage. I love this bike.