I cant give you a link sadly

as most ebay ps2 controllers are fakes..
Ask around locally, you can get an original PS2 controller + adapter for around Rs 500-550
The reason why im recommending this to you is because PS2 controller's buttons are Pressure sensitive..You may use them in racing games as analog triggers unlike a regular gamepad's digital buttons..
However you will need appropriate softwares like MotionInJoy and DS3Tool to configure it properly tho (its a one time thing

)
But if you dont want to go over all of this rabble, just buy a Frontech Gamepad.. I can vouch for it's reliablity