Had given a list to the Ankit dude, of 4850 compatible coolers, called him multiple times and he told me that nothing from my list was available.
Decided to go to SP Road anyway, went to Golcha and to my surprise Scythe Musashi(3.4k) and Thermalright TRad2 GTX(3K) were both available with him. Bought the latter and was surprised to see that Golcha has a good stock of aftermarket coolers both cpu and gpu. Anyway, now my old horse (4850) runs cooler at full load than it used to during idling with the stock cooler. Yay!! BF3 here i come!!