Get a ballistic helmet, if you cant afford or find one, get a motorcycle helmet or even a construction hardhat. The airsoft larp gear will just get you hurt.
Also, and this goes for ballistic plates too, if it ain't NIJ certified it is worthless and will get you killed or injured.
https://www.hardheadveterans.com/blogs/reviews/bulletproof-helmets-what-you-need-to-know
You can pick up a FAST high cut helmet used around 300, and guaranteed to work with any gas mask or respirator you might need. My second choice would either be a construction helmet, just so I could still use gas mask/respirator or a dot rated motorcycle helmet, which you could still use a half mask respirator with unless it's a full face helmet. ( In which case make sure you have good eye protection.)