Just import the Caapi!
You will have AQIS heat treat it. It can take them six weeks.
I have imported so much Caapi over the years it is silly. And so have friends. (lets not go into the kilos and kilos of coca leaf...)
Really, customs don't care. They are not actively looking for this. It is very much an extremely minor and technical import. As far as I know, they are not looking at a list saying "Banisteriopsis Caapi" is prohibited. If so, ask the person shipping it to label it as "ayahuasca vine" or similar.
Harmine, which is in Caapi, is prohibited, but it comes under a TGA schedule, which is a little obscure.
Even if they find it, the worse they will do is confiscate it and send you a little letter telling you of their petty little laws!
If you buy into being a scaredy cat colonial wussbag, you deserve to be starved of Caapi and wither away into sweet caapi less oblivion! ;-)
Therefore - I am not going to sort out anyone for caapi here and support your indoctrinated wussiness!
You only need a few sticks. If you are REALLY paranoid, just order 200 grams from somewhere like maya ethnobotanicals and get it sent to someone O/S and then have them send a few sticks to you in oz sent discretely without any labelling. I have been sent stuff that way which AQUIS didn't get to. So you get it quicker.
Vine makes better Changa imo. You have a nice afterglow afterwards with vine.
The sample that Trout originally tasted in OZ was JUST LEAF and that is a nice way to go. The reason why leaf was used a lot is because we could get it more easily from locally grown vines and we would rather drink the vine, but also vine was used as well - it was just that vine wasn't always around because people would drink it or want it to drink that it would go towards that. Vine leaf being used in some way, was novel and thought special. It is a nice smoke, and has all kinds of qualities and special alkaloids for sure - but for Changa, it is not necessary or better at all.
Vine AND leaf from the same plant is best imo - use 50/50 of each is what I normally like to use.