Haven't tried it, but one thing that springs to mind is the refillable sprayers sold in kitchen stores.
Oh man, you sent me on a rabbit hole of electric dusters, mini-compressors, refillable spray cans, tubeless tires inflators, and PAM substitutes... Here are some brief conclusions:
- People who work in electronics seem to appreciate the electric dusters, which are basically just small vacuum cleaners working in reverse. They're efficient at pushing dust away from computer cases, but can get noisy since they rely on a fan to push air. They will also pump whatever dust is already in the air, so you need to check filters. Could work, but I like my darkroom to be a quiet place.
- There is a LOT of oil spray bottles to replace PAM and other cooking sprays, and they seem to fall into two categories: basic piston systems, like the ones used in bottles of household cleaner (you press and it sprays), and those that can build pressure. They're all designed for a wide jet, but the best candidate would be the systems that build pressure.
- A similar system is used in refillable aerosol systems, usually designed for paint, but it looks like you can build more pressure. You usually connect a bike pump or a compressor hose to them. The final spray is broad, but if the nozzle accepts a straw, you could concentrate the jet.
- Tubeless tires inflator system work the same way: it's a bottle that you fill with pressurized air from a pump, and there is a valve to release it all at once to seat the tire. Key would be the control of pressure release, so that it doesn't blow all at once.
- Finally, small compressors fitted with filters and hose seem to be a pretty useful solution, and surprisingly not that more expensive compared to those electric dusters. But you need the space, the fittings, and it's noisy when the tank fills. They would make a lot of sense in a professional darkroom: get a big tank, install it away from the work space, and run tubings to the working area.
So in the end, I'm tempted by the oil/paint sprayers systems. They look cheap and maybe a bit flimsy, but could be fun to try.