The rule of thumb seems to be:

"the smaller the camera, the bigger the price".

However there are several cameras that fit within your budget; but at the very high end of the budget.

All can be found for about $350.

Casio Z57
Fujifilm Z1
Konical Minolta X60
Nikon S1

The Sony T series of cameras are priced from $450 to $500.

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