The quickest way for this to 'read' as fake money is to print it on white paper. Or think of it this way, your money roll is a cylinder. while the sides will look ok, if not a little flat, the cut edges and the top/bottom will be stark, untutored white.
Go to your local OfficeMax and grab a box of linen textured paper in ivory. For ease of making your bank roll, try printing several bills together as a single piece. You can also try just printing the 1/2 inch of the top and bottom of the bills and by leaving the middle blank or by not printing the middle at all and taping the edges onto some cheap paper(maybe a paper receipt roll) you can save the more expensive paper and/or ink in your printer. Once you have your 'money', make sure to give them some texture by bending/folding/crumpling the paper to replicate the wear and tear real money goes through. Save your most real looking bills for the outside and you got your self a reasonably real looking bank roll.