If the downgrade won't offend you, Shimano's WH-R560 wheelset looks just like you are describing. Silver "areo" rims, 16H laced radial in front, 20H radial ds, 2X nds for the rear. The freehub body, unlike the Ultegra and Dura Ace wheelsets, will accept any 8,9 or 10-speed cassette. These typically sell for less than $200 a set these days.