Is there a limit of profit? Suppose I have a form of unique kind of mango which is the only one kind in the world. Can I sell them at a highest price as I wish or I have any obligations of any percentage of total growing and handling cost as profit? If it has cost me Rs. ten thousand and I wish to sell them on the price of millions or whatever if I get such wealthy buyers? What percentage I can get on the real cost?
The general principle is that you are not allowed to exploit people by overcharging or hoarding a commodity which is a necessity of life and you exploit their plight by overcharging them. If an item isn't a necessity of life and people can live without it, the market forces of demand and supply would determine what the price should be.
In the case of the product you have mentioned, my opinion is that you can charge whatever price you deem fine. If the people would consider it worthy enough, they will pay for it.; otherwise a lack of demand will force you to lower your price.