Free part alert: Allright track guys I have a part you can have for free if you want it. Since I think you guys might actually get some use out of it.
For Free: One Boomba lower engine mount. Used for 8 minutes. hahaha
http://www.boombaracing.com/honda-civic-si-2012-and-up-torque-dampers/
(The short one)
I bought a set of mounts for my car and I ended up deciding that they are not for me. The upper mount won't fit but the lower mount is the same for my car as the 9th gen SI. if anyone would like this part I would be happy to send it to you as it is just sitting around. No fee or money required but, the only thing I would ask is if you would take pics of the install and post a review for us in the DIY section.
I can take some pics of it if you guys would like. It's black and it goes in a place that no one sees it anyway. I know a lot of guys like squiggy and 323 have gone with the Hasport rear mount. That is a great piece as well. If you are unsure of install procedure you could definitely ask one of those guys. It should be pretty simple, just a coupe bolts and I think this can be done easily with the car just on jackstands in your driveway. That's how I did mine the first time when I tried them out.
Let me know.
This is squiggys DIY on the Hasport mount. Look through this as install should be nearly the same.
http://9thcivic.com/forum/threads/2012-civic-si-hasport-rear-motor-mount-installation.9444/
(The short one is what you are getting.)