Keep in mind that is a generic UNIVERSAL-fit cat. This means you will (most likely) have to take it to a muffler shop for them to fit it. It is NOT made or sized especially for the Civic, the Civic Hybrid, or even a Honda. It's very generic. So do get estimates on installing one before heading down this path.
Also, oftentimes these universal ones are of much lesser quality and may not last 50K miles. Consider this in your total costs, although at 165K miles, it may not matter much any more.
Some muffler shops (like Pronto) may offer you a pretty good deal, too. Certainly less than the Honda stealer cat pricing.
Also, you can probably get the genuine Honda cat from another dealer or an online dealer. Check out some of them.
Here's one:
http://www.hondaautomotiveparts.com/...5=EXHAUST+PIPE
The Honda cat is $668.07 here.