I wonder if "no less than $300" still excludes the $299.99 point. If those costs are true, then I see Nintendo going with $299.99. With the bad taste of the 3DS still in Nintendo's mouth, they are going to make sure they charge as little as possible without losing money on the Wii U, especially since consoles aren't as popular as handhelds in Japan.
Also, if the controller is around $50 in materials, then I think it could be priced at $70. Sure, we'd all rather it be lower, but it's not unreasonable, as a Wiimote + Nunchuk + Classic Controller is $80. Nintendo may not make a profit at that price, but the point would be to get controllers in people's hands so they buy multiplayer games. This is, of course, assuming the Wii U supports more than one controller, which is somewhat unlikely.