Can I use Google Analytics to track a specific referrer URL?

I have a Featured Product block on my website's home page. I'd like to track it's efficacy by adding a handle ?referrer=featured to it and then have Google Analytics track checkout on said product.

I'm assuming I'd need to set up a goal to do so, I looked at the options via Admin → Goals → New Goal but can't seem to find anything relevant there.

Will I need to put a specific tracking code in the template page for the product? The tricky bit is that the featured product is changed daily, so I'd like to track if anybody buys any featured product by clicking on the block, hence why I was thinking of the URL handle.

Any ideas? Much appreciated.