An alternative to consider are dot matrix / impact printers.

They are used in kitchens, as heat sensitive paper doesn't work well there. It's just plain paper and an ink ribbon.

Same underlying protocol as thermal printers, so the code is mostly plug and play.

They often can print in two colours (red and black). And sound like the 1980s.

You can buy phenol free paper

https://www.pca.state.mn.us/business-with-us/bpa-and-bps-in-...