The Gaggia should be in that price range and is popular, it has a boiler whereas the Sunbeam is a thermoblock.
With any of these machines you will need a grinder to get good espresso from them. Starting point would be a Sunbeam EM450/480 from $150-200 mark.
The 6910 is popular with CS members and makes a good espresso, they offer a grinder included package occasionally if you keep on the lookout. Price ranges from just under $600 up to $670 mark.