From my understanding, the word "changa" is mostly used to specifically describe enhanced leaf made with DMT and B. Caapi leaves, but I could be wrong. Changa is not my area of expertise.
Parsley is available in the spice section of most grocery stores. I haven't used it personally, but I have read that it works well for enhanced leaf, seeing as it tastes alright and the smoke isn't too harsh. The same goes for mint leaves. I typically use a blend of about 40% mullein, 30%passionflower, 20% skullcap and 10% mint. These all have a very pleasant taste, the smoke is not very harsh, and they all have their own enjoyable qualities.
Mullein- due to its fluffy consistency it soaks up alkaloid-containing solvents very well when you are infusing the leaf.
Passionflower- contains small amounts of MAOI alkaloids, so I only use it when I am making enhanced leaf without adding freebase harmalas. The small amount of MAOI alkaloids in passionflower are not enough for a full MAOI effect, but it is enough to slightly lengthen the experience and slow the onset a little bit.
Skullcap- calms and slightly sedates the nervous system, increasing the likelihood of having a peaceful experience.
Mint is added for flavor.
You really will just have to use whatever is available to you and experiement with different blends until you find one that works best for you. And as 3rdI said, there is an enormous amount of information in the changa section of the forum. Happy travels!