I've heard you can just buy all the tags and licences on Amazon. Airports don't question them (and aren't allowed to because of HIPPA)

I haven't done this, but I know someone who has. The dog has to be well behaved though or else you'll run some risk.

I did exactly what nostr:nprofile1qqsfye65t5530wq0wpllmdz23luhjxp9drhhh2syae6kk8cp6n3k3zsppemhxue69uhkummn9ekx7mp0qyghwumn8ghj7mn0wd68ytnvv9hxgtcdspxda said and flew quite a few times without an issue. However, one flight on Allegiant did refuse to let us on and that makes for a shitty day.

American turned out to be the best because they give your dog a "known traveller" number you can enter when you biy the ticket.

Check Bluesky. They’ll have your roadmap.