Chony,
I am pretty sure that the power cable used on the Tyros is a standard polarized 2 prong cable and can be found out Radio Shack or any place that sells cables.
There is no power transformer. It is internal.
The link you posted is for a non-polarized cable. So don't use it as the Tyros might be sensitive to that, and it is possible to plug in the wrong way.
Try something like this:
http://www.radioshack.com/product/index....rentPage=search