New key for used car

I have just bought Acura TL 2005. This car is without original key with remote control to open/lock dors and trunk. Only key to open dor and start the engine.

Question: where to buy key with remote control for Acura? Someone told me that possible to buy not expencive key on Ebay. I have checked, cuch keys are exist. But how program it to being compartible with my car?

Thank you for detailed answers.