I guess it would technically be possible. This, however, would require you plugging the keyboard into a powered bluetooth module (the keyboard and bluetooth would need power, hence the batteries in the wireless keyboard). So I doubt you'd be able to make some like even looks decent.
I figure, for the time, effort, and money you'd drop into a project like this you'd be MUCH better off just buying a regular bluetooth keyboard. If you need a number pad, go on ebay and buy an old model apple keyboard or a 3rd party one.