Just a notice for you if you found a repairman, if the repairman said that you need to change the DVD-ROM (I wonder why is DVD) for your WiiU he/she is half correct.

You can only change the WiiU Disc lens instead of changing the whole DVD-ROM. Your WiiU won't recognise your new DVD-ROM by simply exchange it.

If you only need the lens/spare DVD-ROM I have a unit here can sell cheaply for you.