How can I get 10mg Omeprazole?

I have GERD, CFS, year round allergies, and a low fiber diet from ARFID. These interact in bad ways.

I might benefit from a lower daily dose of Omeprazole so my stomach can digest more easily (I cough up a lot after eating, I need to be on my back most of the time, and I deal with excessive post nasal drip), but 10 mg Omeprazole is not OTC despite search thinking it is, and you can't cut the pills in half because the delay from the pill coating is necessary.

I'm meeting with my doctor next week and will ask about an Rx dose. I wanted to know if there is an OTC I'm not aware of, or whether 10 mg is likely to require a formulary or would be expensive.