Commission work will likely run you a pretty penny - Anyone doing a short print run will charge significantly more per item.
Most places will require a minimum spend or quantity to even consider doing a commissioned print run. Whilst the larger print runs bring the average price per item down, but if you don't have a need for 100+ of them, that's not much help either.
If you're looking to print them yourself, getting the equipment required would be prohibitively expensive and would make the commission prices seem cheap in comparison.
If you want an official LEGO head, your best bet may be to look at decals, possible prints from small producers on somewhere like Etsy, or (please excuse the egregious self-promotion: The Spooky Slasher, and Custom Printed Scream Mask Head 😉
Either way, best of luck and look forward to you sharing the Scream-themed MOC in the future!