Again - not a hard drive. With the configuration in your signature, if it had Lion it must have been the first/second generation of the Retina MBP, which used a proprietary Apple interface SSD. Some sources seem to have Apple's OEM SSD, while OWC and Transcend sell their own versions.
MacBook Pro 13" Retina (Mid 2012/Early 2013) SSD (661-7008, 661-7009, 661-7010, 661-7011) 128 GB / New - iFixit
MacBook Pro 15" Retina (Mid 2012/Early 2013) SSD (661-6486, 661-6487, 661-6638, 661-7284, 661-7286, 655-1795A, 655-1858A…
OWC SSD Upgrade Kits For MacBook Pro Retina Display (2012 - 2013)
JetDrive™ 820-Transcend Information, Inc.
Here's the instructions. The 15" is the same process. It's kind of odd too, since it looks like the drive bay is big enough for a hard drive, but then there's the SSD in a subassembly that takes up about 2/3 of the bay using a spacer.
MacBook Pro 13" Retina Display Late 2012 SSD Replacement - iFixit
I don't know of any company that sells an SSD complete with operating system unless it comes in a computer. That would generally be a violation of Apple's licensing terms. Only OEMs are allowed to do that, but Apple doesn't license its OS for anyone else's machine. You would need to do it yourself. It should be pretty easy to do it with Internet Recovery, which will allow you to run Disk Utility to format a new drive or reformat yours, then do a clean install of the version of OS X that came with your machine.
I'd recommend getting an external drive and performing regular backups. At least have a bootable clone that you can use to at least operate if the internal drive fails. If you have that it would be really easy to recover.