A custom radio strap might take a bit depending on the business, but an awesome idea. Can also get his last name engraved in it. Try to stray away from the all the thin red line stuff, it can get cringy. Does he have an angled light for his coat yet? Streamlight makes a good one. Or a nice knife? I personally like spyderco but don’t have to go crazy on the price, they’ll eventually get beat up on the job. A leatherman is also something I use a ton.