Talk to White Rose in the UK.
Overflight flight clearance Home
If you can afford the time and money, do it. Don't not have a go.
The trip won't be cheap. The container route will cost US$5Kish. You should expect to pay several magnitudes more than that to fly.
White Rose will get you agents and help you with all the clearances you need. If you have about 700 nm range you can make it, can you stretch that far? An approved ferry tank on the back seat could solve most problems because 800-1200 nm range makes it much easier. Talk about the demise of avgas is a bit premature. There is always a way to find it and White Rose will help.
Probably your biggest problem will be explaining what visa you need in India because you'll need to stop there a few times. India is very expensive for transits and you will have trouble with the food/accom/water. Part of the adventure I'm afraid. Most other countries will be manageable without too many glitches.
White Rose will also tell you how much each airport will cost along the way.
I suggest a rented HF and look to buying the liferaft and jacket.
Talk more on PM if you wish?