ok according to tdays exchange rate 200 euro is 254.773 USD
and for that 254.773 you could get a ma audio amp (M700XE ) and one ma audio 12inch sub ( MA12D4 12" )
you can get 250wrms from each chanel from that amp at 4ohm and just hook up each chanel to each voice coil on the sub ( DVC sub ) and then you will have 500 wrms going to that one sub, and trust me ma audio subs will handle more then they are ratted for, it comes out to 280 or so $ us but save up the 26$ its well worth it, i have 550wrms in my car with one 12 inch sub and my wipers move to the bass slightly, and my box is not even to spec
here are the links for the two items
amp
http://www.sonicelectronix.com/item_6561.html
sub
http://www.sonicelectronix.com/item_4085.html