Limo needed!

My brother is looking for a limo for South Side High School's Prom June 23rd, starting around 5:00 pm. There are six couples so they need at least a 12 pass limo, preferably a little bigger. They need the limo for 10-12 hours (whatever the standard prom time is).
Does anyone have any available?
Any quotes?
Thanks...
Janine