In Italy, Austria and other countries, you can distill with a still which has a 1 litre kettle. This was so even before the recent depenalization in Italy. Gaggia, the famous coffee-machine producer, sold a 1lt distiller for the home (it was introduced together with the first espresso machine for the home, the Baby Gaggia, in the early '80s).
The reason for the 1 litre exemption was due to this kind of innocent work: school experiences, herbal preparations, home-tinctures, water-vapour tinctures, that kind of stuff. Also, all stills with more than 1 litre kettle in theory should be numbered and registered by the producers, in Italy. Stills with 1 litre kettle never had to be numbered and registered.
The US being a strange country, it is possible that this is not allowed, but I do think that, if you read well all the laws, you might find exemptions for tiny stills also in your jurisdictions. Certainly high-school teachers don't need a distilling license, and chemical laboratories, chemists' etc. don't need either. And wine producers (who need to distill to determine the alcohol content precisely) also do "distill" technically.
Read your local norms and you might easily find exemptions for little stills.
PS I see that, in the US, federal laws allow the possession and use of still for non-alcoholic products. So yes, you can make tinctures (extraction in water vapour). I would also say you can re-distill a bought spirit because you are not actually creating a new distillate but you are only manipulating the distillate you bought.