We stayed at Elmore Rv Park when we were there for a game. It's nothing fancy and they will put you up front in the gravel area, but it did the job. Felt safe and close to the stadium and I'm sure it wasn't expensive or I wouldn't have booked it.
But with a van like that, im sure you can find a safe/decent spot to stealth camp. Hopefully others may chime in. Maybe try boondockers welcome..etc.