see if you can't go back to those head shops and ask if they have contact info for any local glass blowers.
get in touch with them and tell them you need a vaporizer, and which specs you would need, they should give you a price. if its reasonable (which it should be) contract them to blow it for you.
i would really recommend you consider getting a convection vape, however (it might even be cheaper to get him to blow a gvg-type burb, and that might work better)
My wind instrument is the bong
CHANGA IN THE BONGA!
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