in your local Big Box Store, look in the "gas fittings" (plumbing dept.) for propane/natural gas appliances.
also in the refrigeration section - all those little brass and plastic fittings might help.
or - the basic brass air hose fitting. you can have a 1/4 or 3/8" line.
you could also pack a little stainless steel wool in the hole to keep the dirt daubers out.
or - solder the hole closed and then drill a 1/32" hole in it to vent.
That's a good idea and I have that fitting from old air tools. I think the "real" thru hull gas vents have bug screens that act as a flame suppressor. Think cigarette in the wind. They also are rigged to shed water but I'm going to look for a place out of the way to just mount a small nipple like that and shove a screen in it. Home brew beats Amazon any day. Thanks for the idea!
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