I've tried heavy duty trigger spray bottles, pump up kitchen spray bottles (which work but kinda peter out quickly (no comments)). and the medium size top pump things that the
"EVIL ORANGE EMPIRE" sells (sorry Vinsect, I own stock too , it's just funnier that way).
Most can't pass the oil at all or won' t mist it and just splat out this weak little stream.
I used to keep large covered coffee can filled with and inch or so of oil. A 3" natural bristle paintbrush with the handle cut off so it would close. I would use this to lube the grates. But it picked up bits and pieces of undesirables and got funky pretty quickly.
Ideas. (NOT PAM)