CineCity have a shoulder mounted camera rig they like to call the FILMCITY I-Shoot shoulder rig.
The camera rig will set you back $377 and comes with its own case.
FILMCITY I-Shoot shoulder rig FEATURES:
Lightweight solution with professional features.
Features 15mm industry standard rods to support professional accessories such as follow focus systems or matte boxes.
Comfortable, angle adjustable handles with slip-free rubber padding.
Simple shoulder support, ideal for run and gun.
Can be used for low shots. Mountable on quick release plates, tripods, sliders, etc. (1/4 and 3/8 inch holes underneath).
Features many accessory connecting points (1/4 inch holes and hot-shoe slots).
See CineCity for more on their FILMCITY I-Shoot shoulder rig.