The OEM brake rotors (ATE I think is the brand) are very good in stopping the car, even with no upgrades. If you're changing the rotors you might want to look at swapping W126 front brakes, if you so decide to (adds ventilated discs instead of the solids). But since you said no performance stuff...
Same sites I gave you before have the OEM rotors.
www.germanstar.net
www.performanceproducts.com
www.autohausaz.com
For pads, OEM brands include:
ATE
Textar
Don't forget to check if the sensors need replacing (you'll need 4, at roughly $1.50 each).
I also have an extra set of front pads (ATE) for my car. Accidentally purchased this extra set (I thought the sets sell for each wheel[

)]). It should fit yours. If you want, you can have it for $40 (original price, still new, NEVER used). PM me if you're interested, Anaheim isn't too far away from Garden Grove.