Surveyors vests have those. Probably draw a lot of attention to yourself wearing hi viz though.

I dunno about drawing attention. I've heard enough stories of physical pentesters getting into secure areas using the "wear a hi-viz vest and a hard hat" strategy. The outfit seems a little like Douglas Adams' "Somebody Else's Problem Field". People seem to be blind to the stereotypical "workman" getup.

Ha! I used to be a land surveyor before I was an engineer. I had one of those vests and yes, I did put a laptop in there a few times during lunch breaks when I didn't want to leave the laptop in the truck.

Field vests for biologists or other folks who work outdoors but not near a highway or construction site have lots of pockets and aren't hi-viz.