Just go to Amazon and flipkart and put your size requirement of around 50". Tvs are normally 48".
to 55".
Select sony, lg and Samsung in filter.
Dont select Nokia, Motorola, OnePlus , etc. These are all rebranded Chinese TVs.
I checked just now and the price range is around 50000.
DONT buy from Amazon or flipkart though. This is just for reference. Physical stores sell the same tvs cheaper. Take the specifications and prices of the tvs you like and go to the physical stores. Now you have reference prices.
I saw a Samsung 4k tv for around 51k on flipkart. Though ppl might say no use of 4k in 50 inches, i personally would not buy a full hd tv now.