I broke the rear glass on my 2007 DK45:smiley_aafz: Mine has the rear wiper, the glass was available with & without the holes for the wiper. It turns out, the glass with the holes was actually cheaper (I guess more demand??) I should mention "cheaper" may be a misnomer!!! (nothing cheap about it!!) As I recall, it was over $500 - with shipping being nearly half the cost!
I know this doesn't answer your question about a 2002 DK50, I'm just saying that I doubt (very) seriously that anyone would likely find it cost effective to purchase all new parts, just for the convenience of a rear wiper. If you are considering it, I sure don't see why you can't just call your local dealer with your model / serial number, and get an availability/cost estimate.
My rear glass was tempered glass, I am assuming yours is to...I would HIGHLY recommend checking on the replacement cost BEFORE you take a drill to it!!