There are tons of cameras out there for that price and in that megapixel range. bhphotovideo.com is a great place to start shopping. Not the lowest price around, but very reputable. Make sure you don't get import models for cheap $$$. It is tough to point you in a certain direction, because in that price range there is so much available. Sounds like you may need something a little more durable...
I'm always partial to the companies that make the higher end SLRs...Nikon, Canon, Fuji, etc.
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