With the optical viewfinder being what the camera will see you are saying that you want a DSLR. Those are the only ones that show the actual scene through the viewfinder. Under $500 will be pretty difficult to do, maybe a used one on Craig's list.
There is just too much to chose from
These are the features I MUST have
1. I must be able to purchase underwater housing so that I can take pictures scuba diving
2. Real image optical zoom viewfinder
These are features I would like to have
1. Wide angle lense
2. rechargeable Battery

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