I found a couple of Matchbox toys which could be useful for games like Infinity. The toys are called SB94 Drones. They are diecast metal, painted in a sporty lime green, with little missiles on pylons moulded under each wing. (Not PC, Matchbox, but no worse than any other armed toy.) They were for sale at a local supermarket, for AUD 3.50 each. Bargain!
The missiles aren't very well moulded but will stand out fine with a good paintjob. The propellers and landing gear are plastic, and they can turn (or at least they would if they weren't gummed up with paint.) The other details such as cameras and panel lines are at the level you'd expect for a toy of this type, just like doors and mirrors on a Matchbox or Hot Wheels car.
Since these are fictional drone aircraft, scale is up to you - they could be anything from model aircraft to airliner size. I have included an old 28mm scale figure for comparison. In a roleplaying or miniatures game these could be props, objectives or actual UAVs.
The Matchbox paintjobs are actually quite thick. If you look closely at the starboard wing of the drone behind the figure in the overhead photo, you can see a chunk of paint is missing from a mid air collision (which happened in my car on the way back from the supermarket). If you were really keen, you could strip the paint off and start again. I didn't bother.
I gave them a coat of Tamiya grey primer, which was the only grey spraypaint I had handy. Next will come some markings, perhaps an Evil Corporation, and picking out panel lines, weapons and surveillance equipment. The underside of the drones has the usual manufacturer's and copyright information, in raised lettering. I didn't bother removing it, but you could probably file it off.