I would look at the Trek 7.2FX. It goes for about 460.00 USD new. It doesn't have the front suspension fork, which at your weight will just be working against your pedaling effort anyway. It does have a suspension seatpost, which you could replace inexpensively. I'm sure there are other brands that offer equivalent models. Check craigslist too. As others have said, you may have to have your spokes and wheels worked on some. Good luck.