"Jinos 3D Filament” is pretty cheap. I started using them during the pandemic when it was hard to find PETG. Seem to be a small place in North Carolina that manufactures mostly for their own use? Sometimes they take a couple of days to ship.
They sell mostly on eBay: https://www.ebay.com/itm/382556327412
[Edit: Just re-read that you’re looking for ABS/ASA - I don’t think Jinos does those, unfortunately]
He is so good at getting subtle facial expression through the prosthetic. Really remarkable.