Another approach is getting a small air tank for refilling at any gas station, or a little home compressor...,
and clean the Mac every 2 month or so.
(There are refillable air spray cans available, but they can contain only about 6 litres of air. So very little.
I don't know how many seconds they last.
They are usually to spray liquids like oil etc., and they use air to drive out the liquids.
Could be refillable with a foot air pump.)