If you are equipted to bill HSAs through your office, you could purchase the peptides with the pharmacy billing the practitioner. Then you can collect the HSA. that may possibly work.
I’m not sure if rules for HSA are different than for MSA but I ‘ve had no problem using an MSA. The managing company most of the time doesn’t even request verification as it’s a pharmacy. Sometimes they have asked for an itemized receipt that shows it’s for a prescription medicine from a pharmacy.