Better than half price, that's £10.08 a meter, you'd probably only need half that for a keyboard rest so you get a spare rest free too
I guess it could work if you are OK working with wood. You'd have to cut to size, stain and match in the cut ends then round off all the corners and add non-slip pads. Even with all that done, the angle of the chamfered part is too much and the sharp edge would be uncomfortable on your hands.
Or you could pay for it completely finished and done for a little bit more.