check your local classifieds; check with a dealer who takes trade-ins. Check with an on-line site such as Craigslist or the auction sites for completed sales.
I don't know how old that model is, but if you go to sears.com there are photos of all the lawn mowers that are currently for sale. Lawn and garden section. Otherwise try EBAY they have lots of lawn mowers and you can narrow down what you're looking ...
I agree, just go with Sears Craftsman. I've had mine for years, and she still cranks up, right away. If you're going with self propelled, be sure to get large rear tires with the front wheel drive. They are much easier to turn, than rear wheel drive....