I’ve usually just walked into a local pharmacy and asked if they have the booster. My local pharmacy just has a standard paper form for all vaccination (flu, shingles, covid, etc) walk ins, there is no website or arbitration clause or even specific covid form. You might want to try a different pharmacy if that has been your experience.
I just hope they don’t cost an exorbitant price now that the national health emergency has ended here. It was really nice being able to get them for free because I am poor.