yea i made mine... but you can buy them, headshops have them sometimes... cost you about the same to make one as buy one tho... well atleast my way, i used an acrylic bong i had (cost about 20$) and the gas mask costed about 20$ (i didn't buy it or pay for it, i just know that's about how much it costed)
that's 40$ and my local headshop sells a couple diffrent styles for 45$