Definite OEM look: the CD/CDR220 and CD/CDR210. Both work in the 968 once you have had the faceplate mod done. These units are made by Becker for Porsche and are OEM. The reason you need the faceplate mod is because the mounting angle of the head unit precludes you from easily viewing the display while in the car.
The CDR220 can be had from Harman/Becker in NJ for under $300 I believe (refurbed, with factory warranty). The faceplate mod sets you back another $100. You can buy an iPod adapter online which will feed the iPod to the head unit via the AUX channel. It will also charge the iPod. These adapters are available from manufacturers like P.I.E. Do not buy the adapters from Becker- it is merely an RCA AUX input- will not charge the iPod and you need to convert the iPod jack to RCA plugs as well.
Newer Beckers are also suitable for an OEM look. Availability and price are considerations though.
Blaupunkt also has nice units which look more OEM than others (like Jamie's).
I am leaning towards Pioneer when my time comes. I really like the DEH-P410UB and the DEH-P510UB. I am hoping the organic displays on these units can be seen in the 968.... I really like the direct USB/iPod connectivity of these units. I can run the iPod cable behind the dash and under the armrest cover or into the glove box and the iPod is out of sight and completely controlled by the head unit. These two Pioneers can be had for under $175 each via Sleezebay and such. Plus they still play CDs.
Bottom line- there are quite a few choices out there which can look OEM. Really just matters what functionality you want and how much you want to spend.
If money were no object for me, I would end up with a Becker Grand Prix with the optional iPod adapter kit - really looks OEM and has the necessary functionality, built in, for me. Not sure if the viewing angle would be problematic though!