Sorry if I answer again, but I realize I forgot to mention it: before there were SSRIs, there were MAOIs (monoamine oxidase inhibitors) as treatment for depression. There were abandoned relatively quickly as full-scale MAOIs require a pretty strict diet or they can be deadly. Research on them has restarted again more recently as there exists selective MAOIs that only inhibit MAO-A and are fully reversible in a matter of hours - compared to weeks for traditional pharmaceutical MAOIs.

One of those selective, reversible MAOIs is harmine (and harmal alkaloids in general, like harmaline) - a substance produced by a number of plants. It does not require any special diet and is used traditionally by tribes in the Amazon to prepare Ayahuasca - the MAOI effect makes DMT orally active, for several hours. It is also commonly used today in western countries by people doing shrooms or DMT, as it increases the effect of both and makes the later orally active. It has demonstrated antidepressant effects without the risks of the aforementioned pharmaceutical MAOIs, and is now the subject of active further research for those uses.

Now, there is a plant, Peganum Harmala, more commonly called Syrian Rue, which produces seeds that contains tons of harmal alkaloids. It's not the plant Amazon tribes use (that would be Banisteriopsis Caapi), but its seeds have a very similar alkaloids profile. It is extensively used in Iran and other middle-east countries, both in cooking and for medicinal effects.

Do you live in the US ? if so, finding syrian rue seeds is incredibly easy and very cheap - look for "Esphand", another name for it. You can also order them online, they're perfectly legal in the US. If you get those seeds, the basic mode of administration is: crush them into a powder, make a tea with them, filter, and drink. 3g of seeds is a good dose.

Be aware that the harmal alkaloids in question are psychedelic by themselves; but usually at amounts closer to 4g/5g tea, and with side effects (specifically motor dysfunction and nausea - those side effects tend to disappear if you use it enough, though, but for a 3g tea they should be minimal anyway). If you're looking for medicine, this is also definitely worth a try. Drink in the morning, effects last for at least 4 hours. If you notice too much side effects at 3g, go for a 2g tea.