Graphics Card Change?

You do not have a "card."

Since its introduction in 2006, the MacBook Pro has used graphics hardware that is integral with the logic board. Never had a "card." To change the gfx hardware you have to replace the logic board. And there are no logic boards compatible with your model whose gfx hardware is more powerful than what you now have. You are looking at your "forever graphics."

The bus specs are available in System Information (in Applications > Utilities). Run it and select "Graphics/Displays" from the left-hand contents pane. I'm typing on an iMac at the moment but yours should should information similar to this:

Very interesting. My engineer's eye says that very nifty solder/desolder machine would have a price tag between US$25,000 and $40,000 so, if you don't have one stashed in the shed, you are welcome to send your computer to the people who presented the video. Frankly the pricing they quote is a bargain.

I would use their "send the complete computer" option because stripping out the logic board is not a trivial matter in those notebooks.

http://www.powerbookmedic.com/xcart1/pages.php?pageid=67

I would call them at the number on that page to make sure they still have the parts.