Help - somehow lost the vented filler plug off the steering box

Greased the steering box yesterday, had the two plugs sitting on a rag on the cowl while I squeezed the grease gun 47 times… grabbed the other plug, screwed it in by hand…went to grab the vent fuller plug to do the same… not there… ok fine it must’ve fell,… not on the floor under the car… obviously got hung up somewhere under the hood… can’t see it anywhere… looked all over the garage floor, shook the car, started the car, jacked the car up and got underneath for a look, had my hands, screwdriver, cardboard, trouble light, extension magnet into every nook and cranny above and below… Nothing. I’ve spent hours looking, yesterday and today, bout given it up for gone. I imagine trying to find this part will be next to impossible as it would have to come off another steering box? Can I just use an unvented plug, believe it’s 5/8-24? Could I just drill a small hole through it to allow for venting? Damn this is aggravating.

I would call Chockostang to see if they would sell one.