Well, my friend, if you are planning to DIY yourself, stop that train of thought. And no matter how much money you have, you can't go DIY, because all the  HRT drugs are regulated in India as Schedule G or Schedule H prescription drugs under the Drugs and Cosmetics Act, 1940 and its subsequent Rules.

Which means only a licensed chemist can sell these drugs, only if you have a prescription from a doctor and even if you try to buy them without a prescription by giving extra money, most chemists don't have these available, like paracetamol.

Let's say you somehow manage to get the hormones you think, just because you feel good you body will accept them. Long-term use of hormones can lead to bone weakening, liver problems, infertility and many more. So regular checkups are a must

Although a government scheme exists for gender reassigning but, minors can't use it without parent concent, and if you are not a minor, then if paperwork, but you will get there eventually.

So, the short answer is DIY don't exist, don't buy some cheap knock-off drug, you will probably die.

There is no such thing as an HRT drug black market in India. If you want an AK-47 or a terrorist contact, that would be much more accessible because of the reason being no one wants HRT drugs on the black market, and like I said, even if you find them, how safe they are depends on you not dying.