You could find an older D model ZZR for that money.
D model
http://www.ebay.co.uk/itm/kawasaki-z...item43d383af2d
Or E model
http://www.ebay.co.uk/itm/1995-KAWAS...item5415a00d92
More grins than a GS500 which I promise you is a bike that will make you want to claw your eyeballs out and hack off your throttle hand with a spoon.