https://www.walmart.com/ip/Equate-First-Aid-Iodine-Antiseptic-Liquid-8-fl-oz/236247392
And they have some cheap saline nasal spray...these bottles might be refillable with a DIY 1% povidone iodine solution...
https://www.walmart.com/ip/Equate-Saline-Nasal-Sodium-Chloride-3-fl-Oz/997275726
You could probably find a nasal spray bottle or small bottle of saline nasal spray at a dollar store.
Don’t use the betadine solution full strength, dilute it to 1%
i.e. 1oz of 10% betadine solution into 9oz water
or 1ml added to 9ml of water...etc
If the nasal spray bottles you have do not have a removable cap just make up some solution, squeeze the empty bottle and then hold it in the solution and release...the solution will suck up into the bottle.
The video below suggests a 10 to 1 mixture and that is fine but a 9 to 1 solution will be exactly accurate...but the video is close enough. I don’t think you need to throw out the solution after a day or so like the video suggests... I don’t see how a betadine solution could go bad that fast...lol that would be a very short shelf life, you would have to be at the betadine factory to use some on the spot...ha
https://odysee.com/@FrontlineCovid19CriticalCareAlliance:c/How-to-make-a-nose-drop-solution:7
We don’t discard ours until it’s empty.
Have been making/using, for months.