You can get a good deal off eBay for the windshield and the seat belts, the shipping in the roof might be to high though.
One thing I learned from a buddy of mine that just got his rzr last fall, if your say around 5'6" or shorter, you will have trouble seeing through the half windshield once it gets dirty and scratched up. I'm 5' 10" and have no problem seeing over mine. Something to keep in mind.