M276- Airbox Rubber Mounts/Dampers
As seen here these pieces slip onto both bottom ends of the airbox, and then slipped onto brackets mounted on the engine.
12-16 Mercedes W204 C300 E350 M276 Air Intake Cleaner Filter Housing Box | eBay
Mine are torn as depicted there.




I like the suggestion of @JohnCC about using rubber hose, but it might take layering 2 or 3 different hose sizes.






