Max Dough Weight in an 8.5" Oval Banneton?

I recently bought an oval banneton that is 8-1/2" long, 5-3/8" wide, 3" high from Fantes.  I guess I didn't realize how small it'd be in real life.  What weight dough can be proofed in this banneton?  Since it cost me nearly $20, I'm considering returning it for a larger size.