Pacesetter MONZA is a 2.5" catback and its pretty inexpensive too...
http://www.pacesetterexhaust.com/monza.htm
on a side note, I was reading in Sport Compact Mag. that after 2.5" you loose some low end torque because of the very low back pressure. they had more gains with a 2.25" than the 3" or 2.5", unless you go FI. however, it was the 2.0si that they were refering to in that article...so is this true or what?