RE: Can you use 10w-30 motor oil for air filter
ANY oil will work better than no oil on the air filter.
It would only get sucked into the engine if you are dumb and use too much oil.
A sticky oil will do a better job of trapping the smallest particles though. ARO is sticky and made for the job but there are several other alternatives that are better than regular motor oil. Motorcycle air filter oil works well and is less expensive in the long run but you have to buy it in like pint or quart sizes and that much would last like 50 years... Another good alternative is chain saw bar oil, that stuff is sticky and does a great job too. If you or someone you know has a chain saw ask them to give you an ounce or two and save the $5-$8 ARO costs for the same amount.
But, if you have nothing else, ANY oil is better than nothing!