The picture is pretty dark... It looks like some chrome push guards clamped onto the OEM bumper. If that is the case I am not aware of any vendor that made them specifically for emergency services. Check out JC Whitney, they would be my first guess to carry something close to them.
they were also a stock option on the 73-87 chevy trucks , suburbans and blazers a little longer till the changed the body style depending on what year you are working on
Back in the day before everything went to plastic, you could readily find those bumper guards at your local Walmart or Kmart. Nowadays, your best bet is a auto parts store like Pep Boys, Advanced Auto, Autozone, or something similar.
What year and model are you looking to put a set on? I probably have a set if its a 73-87 Chevy/GMC pickup/K-5 Blazer/Suburban. They were optional/package-standard in that era.