All are good comments. In my experience with the professional services industry (my background), the expected purchase price would be 2.5X revenue. So that would be 2.5 x 60,000 = $150,000. Of course that is a different industry and this one has certain risk factors associated with it that might drive the price down. But, the industry is also experience explosive growth, which could drive the price up. Like others have said, it depends on the buyer and what they intend to do with the site.
You could also sell your current site, take everything you have learned, and start another site and be up to the same revenue in a year or less.