by the way bro. when I change my MBP hdd I only use philips precision screw driver and torx. Torx screws are just extra protrusion for the notch (You can even use pliers or by hand if it's not tight). both tools are very common.
I'm not sure about the data doubler. It's a third party accessory that is available on OWC upgrade kits and not common. Not sure if ifixit has it. I did install a second drive (SSD) on my iMac but I retained the optical drive. I just used 3M double sided tape to secure it at the back of the latter. If i'm not mistaken the data double is just a securing rack to properly mount the HDD from optical drive bay. If so, might as well you can just stick it using 3M double sided tape
w/o the doubler.