I think I'll get some sheets from this place
http://www.isigndesigner.com/index.php?mode=aainstantsign&sid=c968694442e0e86d8 25188d44433ce7a
just uncheck the "border" color and click on the "white" to the right of the Background and you can get pretty much get the exact color you want.
I'd just get the colored sheets with nothing on them.