If your are lookingn for OEM seats with integrated seat belts start looking at the convertible seats. Most of the high end convertibles have seats with integrated seat belts. The BMW E46 (M3, etc)
convertible seats have integrated seat belts.
Check out these threads on pro-touring for more info on the BMW seats.
http://www.pro-touring.com/forum/sho...nvertible+seat
http://www.pro-touring.com/forum/sho...&postcount=356